1Fsdb(3) User Contributed Perl Documentation Fsdb(3)
2
3
4
6 Fsdb - a flat-text database for shell scripting
7
9 Fsdb, the flatfile streaming database is package of commands for
10 manipulating flat-ASCII databases from shell scripts. Fsdb is useful
11 to process medium amounts of data (with very little data you'd do it by
12 hand, with megabytes you might want a real database). Fsdb was known
13 as as Jdb from 1991 to Oct. 2008.
14
15 Fsdb is very good at doing things like:
16
17 · extracting measurements from experimental output
18
19 · examining data to address different hypotheses
20
21 · joining data from different experiments
22
23 · eliminating/detecting outliers
24
25 · computing statistics on data (mean, confidence intervals,
26 correlations, histograms)
27
28 · reformatting data for graphing programs
29
30 Fsdb is built around the idea of a flat text file as a database. Fsdb
31 files (by convention, with the extension .fsdb), have a header
32 documenting the schema (what the columns mean), and then each line
33 represents a database record (or row).
34
35 For example:
36
37 #fsdb experiment duration
38 ufs_mab_sys 37.2
39 ufs_mab_sys 37.3
40 ufs_rcp_real 264.5
41 ufs_rcp_real 277.9
42
43 Is a simple file with four experiments (the rows), each with a
44 description, size parameter, and run time in the first, second, and
45 third columns.
46
47 Rather than hand-code scripts to do each special case, Fsdb provides
48 higher-level functions. Although it's often easy throw together a
49 custom script to do any single task, I believe that there are several
50 advantages to using Fsdb:
51
52 · these programs provide a higher level interface than plain Perl, so
53
54 ** Fewer lines of simpler code:
55
56 dbrow '_experiment eq "ufs_mab_sys"' | dbcolstats duration
57
58 Picks out just one type of experiment and computes statistics
59 on it, rather than:
60
61 while (<>) { split; $sum+=$F[1]; $ss+=$F[1]**2; $n++; }
62 $mean = $sum / $n; $std_dev = ...
63
64 in dozens of places.
65
66 · the library uses names for columns, so
67
68 ** No more $F[1], use "_duration".
69
70 ** New or different order columns? No changes to your scripts!
71
72 Thus if your experiment gets more complicated with a size
73 parameter, so your log changes to:
74
75 #fsdb experiment size duration
76 ufs_mab_sys 1024 37.2
77 ufs_mab_sys 1024 37.3
78 ufs_rcp_real 1024 264.5
79 ufs_rcp_real 1024 277.9
80 ufs_mab_sys 2048 45.3
81 ufs_mab_sys 2048 44.2
82
83 Then the previous scripts still work, even though duration is now
84 the third column, not the second.
85
86 · A series of actions are self-documenting (each program records what
87 it does).
88
89 ** No more wondering what hacks were used to compute the final
90 data, just look at the comments at the end of the output.
91
92 For example, the commands
93
94 dbrow '_experiment eq "ufs_mab_sys"' | dbcolstats duration
95
96 add to the end of the output the lines
97 # | dbrow _experiment eq "ufs_mab_sys"
98 # | dbcolstats duration
99
100 · The library is mature, supporting large datasets (more than 100GB),
101 corner cases, error handling, backed by an automated test suite.
102
103 ** No more puzzling about bad output because your custom script
104 skimped on error checking.
105
106 ** No more memory thrashing when you try to sort ten million
107 records.
108
109 · Fsdb-2.x supports Perl scripting (in addition to shell scripting),
110 with libraries to do Fsdb input and output, and easy support for
111 pipelines. The shell script
112
113 dbcol name test1 | dbroweval '_test1 += 5;'
114
115 can be written in perl as:
116
117 dbpipeline(dbcol(qw(name test1)), dbroweval('_test1 += 5;'));
118
119 (The disadvantage is that you need to learn what functions Fsdb
120 provides.)
121
122 Fsdb is built on flat-ASCII databases. By storing data in simple text
123 files and processing it with pipelines it is easy to experiment (in the
124 shell) and look at the output. To the best of my knowledge, the
125 original implementation of this idea was "/rdb", a commercial product
126 described in the book UNIX relational database management: application
127 development in the UNIX environment by Rod Manis, Evan Schaffer, and
128 Robert Jorgensen (and also at the web page <http://www.rdb.com/>).
129 Fsdb is an incompatible re-implementation of their idea without any
130 accelerated indexing or forms support. (But it's free, and probably
131 has better statistics!).
132
133 Fsdb-2.x will exploit multiple processors or cores, and provides Perl-
134 level support for input, output, and threaded-pipelines. (As of
135 Fsdb-2.44 it no longer uses Perl threading, just processes, since they
136 are faster.)
137
138 Installation instructions follow at the end of this document. Fsdb-2.x
139 requires Perl 5.8 to run. All commands have manual pages and provide
140 usage with the "--help" option. All commands are backed by an
141 automated test suite.
142
143 The most recent version of Fsdb is available on the web at
144 <http://www.isi.edu/~johnh/SOFTWARE/FSDB/index.html>.
145
147 2.66, 2018-12-20 Critical bug fix in dbjoin.
148 BUG FIX
149 Removed old tests from MANIFEST. (Thanks to Hang Guo for reporting
150 this bug.)
151
152 IMPROVEMENT
153 Errors for non-existing input files now include the bad filename
154 (before: "cannot setup filehandle", now: "cannot open input: cannot
155 open TEST/bad_filename").
156
157 BUG FIX
158 Hash joins with three identical rows were failing with the
159 assertion failure "internal error: confused about overflow" due to
160 a now-fixed bug.
161
163 executive summary
164 what's new
165 README CONTENTS
166 installation
167 basic data format
168 basic data manipulation
169 list of commands
170 another example
171 a gradebook example
172 a password example
173 history
174 related work
175 release notes
176 copyright
177 comments
178
180 Fsdb now uses the standard Perl build and installation from
181 ExtUtil::MakeMaker(3), so the quick answer to installation is to type:
182
183 perl Makefile.PL
184 make
185 make test
186 make install
187
188 Or, if you want to install it somewhere else, change the first line to
189
190 perl Makefile.PL PREFIX=$HOME
191
192 and it will go in your home directory's bin, etc. (See
193 ExtUtil::MakeMaker(3) for more details.)
194
195 Fsdb requires perl 5.8 or later.
196
197 A test-suite is available, run it with
198
199 make test
200
201 A FreeBSD port to Fsdb is available, see
202 <http://www.freshports.org/databases/fsdb/>.
203
204 A Fink (MacOS X) port is available, see
205 <http://pdb.finkproject.org/pdb/package.php/fsdb>. (Thanks to Lars
206 Eggert for maintaining this port.)
207
209 These programs are based on the idea storing data in simple ASCII
210 files. A database is a file with one header line and then data or
211 comment lines. For example:
212
213 #fsdb account passwd uid gid fullname homedir shell
214 johnh * 2274 134 John_Heidemann /home/johnh /bin/bash
215 greg * 2275 134 Greg_Johnson /home/greg /bin/bash
216 root * 0 0 Root /root /bin/bash
217 # this is a simple database
218
219 The header line must be first and begins with "#h". There are rows
220 (records) and columns (fields), just like in a normal database.
221 Comment lines begin with "#". Column names are any string not
222 containing spaces or single quote (although it is prudent to keep them
223 alphanumeric with underscore).
224
225 By default, columns are delimited by whitespace. With this default
226 configuration, the contents of a field cannot contain whitespace.
227 However, this limitation can be relaxed by changing the field separator
228 as described below.
229
230 The big advantage of simple flat-text databases is that it is usually
231 easy to massage data into this format, and it's reasonably easy to take
232 data out of this format into other (text-based) programs, like gnuplot,
233 jgraph, and LaTeX. Think Unix. Think pipes. (Or even output to Excel
234 and HTML if you prefer.)
235
236 Since no-whitespace in columns was a problem for some applications,
237 there's an option which relaxes this rule. You can specify the field
238 separator in the table header with "-F x" where "x" is a code for the
239 new field separator. A full list of codes is at dbfilealter(1), but
240 two common special values are "-F t" which is a separator of a single
241 tab character, and "-F S", a separator of two spaces. Both allowing
242 (single) spaces in fields. An example:
243
244 #fsdb -F S account passwd uid gid fullname homedir shell
245 johnh * 2274 134 John Heidemann /home/johnh /bin/bash
246 greg * 2275 134 Greg Johnson /home/greg /bin/bash
247 root * 0 0 Root /root /bin/bash
248 # this is a simple database
249
250 See dbfilealter(1) for more details. Regardless of what the column
251 separator is for the body of the data, it's always whitespace in the
252 header.
253
254 There's also a third format: a "list". Because it's often hard to see
255 what's columns past the first two, in list format each "column" is on a
256 separate line. The programs dblistize and dbcolize convert to and from
257 this format, and all programs work with either formats. The command
258
259 dbfilealter -R C < DATA/passwd.fsdb
260
261 outputs:
262
263 #fsdb -R C account passwd uid gid fullname homedir shell
264 account: johnh
265 passwd: *
266 uid: 2274
267 gid: 134
268 fullname: John_Heidemann
269 homedir: /home/johnh
270 shell: /bin/bash
271
272 account: greg
273 passwd: *
274 uid: 2275
275 gid: 134
276 fullname: Greg_Johnson
277 homedir: /home/greg
278 shell: /bin/bash
279
280 account: root
281 passwd: *
282 uid: 0
283 gid: 0
284 fullname: Root
285 homedir: /root
286 shell: /bin/bash
287
288 # this is a simple database
289 # | dblistize
290
291 See dbfilealter(1) for more details.
292
294 A number of programs exist to manipulate databases. Complex functions
295 can be made by stringing together commands with shell pipelines. For
296 example, to print the home directories of everyone with ``john'' in
297 their names, you would do:
298
299 cat DATA/passwd | dbrow '_fullname =~ /John/' | dbcol homedir
300
301 The output might be:
302
303 #fsdb homedir
304 /home/johnh
305 /home/greg
306 # this is a simple database
307 # | dbrow _fullname =~ /John/
308 # | dbcol homedir
309
310 (Notice that comments are appended to the output listing each command,
311 providing an automatic audit log.)
312
313 In addition to typical database functions (select, join, etc.) there
314 are also a number of statistical functions.
315
316 The real power of Fsdb is that one can apply arbitrary code to rows to
317 do powerful things.
318
319 cat DATA/passwd | dbroweval '_fullname =~ s/(\w+)_(\w+)/$2,_$1/'
320
321 converts "John_Heidemann" into "Heidemann,_John". Not too much more
322 work could split fullname into firstname and lastname fields.
323
325 An advantage of Fsdb is that you can talk about columns by name
326 (symbolically) rather than simply by their positions. So in the above
327 example, "dbcol homedir" pulled out the home directory column, and
328 "dbrow '_fullname =~ /John/'" matched against column fullname.
329
330 In general, you can use the name of the column listed on the "#fsdb"
331 line to identify it in most programs, and _name to identify it in code.
332
333 Some alternatives for flexibility:
334
335 · Numeric values identify columns positionally, numbering from 0. So
336 0 or _0 is the first column, 1 is the second, etc.
337
338 · In code, _last_columnname gets the value from columname's previous
339 row.
340
341 See dbroweval(1) for more details about writing code.
342
344 Enough said. I'll summarize the commands, and then you can experiment.
345 For a detailed description of each command, see a summary by running it
346 with the argument "--help" (or "-?" if you prefer.) Full manual pages
347 can be found by running the command with the argument "--man", or
348 running the Unix command "man dbcol" or whatever program you want.
349
350 TABLE CREATION
351 dbcolcreate
352 add columns to a database
353
354 dbcoldefine
355 set the column headings for a non-Fsdb file
356
357 TABLE MANIPULATION
358 dbcol
359 select columns from a table
360
361 dbrow
362 select rows from a table
363
364 dbsort
365 sort rows based on a set of columns
366
367 dbjoin
368 compute the natural join of two tables
369
370 dbcolrename
371 rename a column
372
373 dbcolmerge
374 merge two columns into one
375
376 dbcolsplittocols
377 split one column into two or more columns
378
379 dbcolsplittorows
380 split one column into multiple rows
381
382 dbfilepivot
383 "pivots" a file, converting multiple rows corresponding to the same
384 entity into a single row with multiple columns.
385
386 dbfilevalidate
387 check that db file doesn't have some common errors
388
389 COMPUTATION AND STATISTICS
390 dbcolstats
391 compute statistics over a column (mean,etc.,optionally median)
392
393 dbmultistats
394 group rows by some key value, then compute stats (mean, etc.) over
395 each group (equivalent to dbmapreduce with dbcolstats as the
396 reducer)
397
398 dbmapreduce
399 group rows (map) and then apply an arbitrary function to each group
400 (reduce)
401
402 dbrvstatdiff
403 compare two samples distributions (mean/conf interval/T-test)
404
405 dbcolmovingstats
406 computing moving statistics over a column of data
407
408 dbcolstatscores
409 compute Z-scores and T-scores over one column of data
410
411 dbcolpercentile
412 compute the rank or percentile of a column
413
414 dbcolhisto
415 compute histograms over a column of data
416
417 dbcolscorrelate
418 compute the coefficient of correlation over several columns
419
420 dbcolsregression
421 compute linear regression and correlation for two columns
422
423 dbrowaccumulate
424 compute a running sum over a column of data
425
426 dbrowcount
427 count the number of rows (a subset of dbstats)
428
429 dbrowdiff
430 compute differences between a columns in each row of a table
431
432 dbrowenumerate
433 number each row
434
435 dbroweval
436 run arbitrary Perl code on each row
437
438 dbrowuniq
439 count/eliminate identical rows (like Unix uniq(1))
440
441 dbfilediff
442 compare fields on rows of a file (something like Unix diff(1))
443
444 OUTPUT CONTROL
445 dbcolneaten
446 pretty-print columns
447
448 dbfilealter
449 convert between column or list format, or change the column
450 separator
451
452 dbfilestripcomments
453 remove comments from a table
454
455 dbformmail
456 generate a script that sends form mail based on each row
457
458 CONVERSIONS
459 (These programs convert data into fsdb. See their web pages for
460 details.)
461
462 cgi_to_db
463 <http://stein.cshl.org/boulder/>
464
465 combined_log_format_to_db
466 <http://httpd.apache.org/docs/2.0/logs.html>
467
468 html_table_to_db
469 HTML tables to fsdb (assuming they're reasonably formatted).
470
471 kitrace_to_db
472 <http://ficus-www.cs.ucla.edu/ficus-members/geoff/kitrace.html>
473
474 ns_to_db
475 <http://mash-www.cs.berkeley.edu/ns/>
476
477 sqlselect_to_db
478 the output of SQL SELECT tables to db
479
480 tabdelim_to_db
481 spreadsheet tab-delimited files to db
482
483 tcpdump_to_db
484 (see man tcpdump(8) on any reasonable system)
485
486 xml_to_db
487 XML input to fsdb, assuming they're very regular
488
489 (And out of fsdb:)
490
491 db_to_csv
492 Comma-separated-value format from fsdb.
493
494 db_to_html_table
495 simple conversion of Fsdb to html tables
496
497 STANDARD OPTIONS
498 Many programs have common options:
499
500 -? or --help
501 Show basic usage.
502
503 -N on --new-name
504 When a command creates a new column like dbrowaccumulate's "accum",
505 this option lets one override the default name of that new column.
506
507 -T TmpDir
508 where to put tmp files. Also uses environment variable TMPDIR, if
509 -T is not specified. Default is /tmp.
510
511 Show basic usage.
512
513 -c FRACTION or --confidence FRACTION
514 Specify confidence interval FRACTION (dbcolstats, dbmultistats,
515 etc.)
516
517 -C S or "--element-separator S"
518 Specify column separator S (dbcolsplittocols, dbcolmerge).
519
520 -d or --debug
521 Enable debugging (may be repeated for greater effect in some
522 cases).
523
524 -a or --include-non-numeric
525 Compute stats over all data (treating non-numbers as zeros). (By
526 default, things that can't be treated as numbers are ignored for
527 stats purposes)
528
529 -S or --pre-sorted
530 Assume the data is pre-sorted. May be repeated to disable
531 verification (saving a small amount of work).
532
533 -e E or --empty E
534 give value E as the value for empty (null) records
535
536 -i I or --input I
537 Input data from file I.
538
539 -o O or --output O
540 Write data out to file O.
541
542 --header H
543 Use H as the full Fsdb header, rather than reading a header from
544 then input. This option is particularly useful when using Fsdb
545 under Hadoop, where split files don't have heades.
546
547 --nolog.
548 Skip logging the program in a trailing comment.
549
550 When giving Perl code (in dbrow and dbroweval) column names can be
551 embedded if preceded by underscores. Look at dbrow(1) or dbroweval(1)
552 for examples.)
553
554 Most programs run in constant memory and use temporary files if
555 necessary. Exceptions are dbcolneaten, dbcolpercentile, dbmapreduce,
556 dbmultistats, dbrowsplituniq.
557
559 Take the raw data in "DATA/http_bandwidth", put a header on it
560 ("dbcoldefine size bw"), took statistics of each category
561 ("dbmultistats -k size bw"), pick out the relevant fields ("dbcol size
562 mean stddev pct_rsd"), and you get:
563
564 #fsdb size mean stddev pct_rsd
565 1024 1.4962e+06 2.8497e+05 19.047
566 10240 5.0286e+06 6.0103e+05 11.952
567 102400 4.9216e+06 3.0939e+05 6.2863
568 # | dbcoldefine size bw
569 # | /home/johnh/BIN/DB/dbmultistats -k size bw
570 # | /home/johnh/BIN/DB/dbcol size mean stddev pct_rsd
571
572 (The whole command was:
573
574 cat DATA/http_bandwidth |
575 dbcoldefine size |
576 dbmultistats -k size bw |
577 dbcol size mean stddev pct_rsd
578
579 all on one line.)
580
581 Then post-process them to get rid of the exponential notation by adding
582 this to the end of the pipeline:
583
584 dbroweval '_mean = sprintf("%8.0f", _mean); _stddev = sprintf("%8.0f", _stddev);'
585
586 (Actually, this step is no longer required since dbcolstats now uses a
587 different default format.)
588
589 giving:
590
591 #fsdb size mean stddev pct_rsd
592 1024 1496200 284970 19.047
593 10240 5028600 601030 11.952
594 102400 4921600 309390 6.2863
595 # | dbcoldefine size bw
596 # | dbmultistats -k size bw
597 # | dbcol size mean stddev pct_rsd
598 # | dbroweval { _mean = sprintf("%8.0f", _mean); _stddev = sprintf("%8.0f", _stddev); }
599
600 In a few lines, raw data is transformed to processed output.
601
602 Suppose you expect there is an odd distribution of results of one
603 datapoint. Fsdb can easily produce a CDF (cumulative distribution
604 function) of the data, suitable for graphing:
605
606 cat DB/DATA/http_bandwidth | \
607 dbcoldefine size bw | \
608 dbrow '_size == 102400' | \
609 dbcol bw | \
610 dbsort -n bw | \
611 dbrowenumerate | \
612 dbcolpercentile count | \
613 dbcol bw percentile | \
614 xgraph
615
616 The steps, roughly: 1. get the raw input data and turn it into fsdb
617 format, 2. pick out just the relevant column (for efficiency) and sort
618 it, 3. for each data point, assign a CDF percentage to it, 4. pick out
619 the two columns to graph and show them
620
622 The first commercial program I wrote was a gradebook, so here's how to
623 do it with Fsdb.
624
625 Format your data like DATA/grades.
626
627 #fsdb name email id test1
628 a a@ucla.example.edu 1 80
629 b b@usc.example.edu 2 70
630 c c@isi.example.edu 3 65
631 d d@lmu.example.edu 4 90
632 e e@caltech.example.edu 5 70
633 f f@oxy.example.edu 6 90
634
635 Or if your students have spaces in their names, use "-F S" and two
636 spaces to separate each column:
637
638 #fsdb -F S name email id test1
639 alfred aho a@ucla.example.edu 1 80
640 butler lampson b@usc.example.edu 2 70
641 david clark c@isi.example.edu 3 65
642 constantine drovolis d@lmu.example.edu 4 90
643 debrorah estrin e@caltech.example.edu 5 70
644 sally floyd f@oxy.example.edu 6 90
645
646 To compute statistics on an exam, do
647
648 cat DATA/grades | dbstats test1 |dblistize
649
650 giving
651
652 #fsdb -R C ...
653 mean: 77.5
654 stddev: 10.84
655 pct_rsd: 13.987
656 conf_range: 11.377
657 conf_low: 66.123
658 conf_high: 88.877
659 conf_pct: 0.95
660 sum: 465
661 sum_squared: 36625
662 min: 65
663 max: 90
664 n: 6
665 ...
666
667 To do a histogram:
668
669 cat DATA/grades | dbcolhisto -n 5 -g test1
670
671 giving
672
673 #fsdb low histogram
674 65 *
675 70 **
676 75
677 80 *
678 85
679 90 **
680 # | /home/johnh/BIN/DB/dbhistogram -n 5 -g test1
681
682 Now you want to send out grades to the students by e-mail. Create a
683 form-letter (in the file test1.txt):
684
685 To: _email (_name)
686 From: J. Random Professor <jrp@usc.example.edu>
687 Subject: test1 scores
688
689 _name, your score on test1 was _test1.
690 86+ A
691 75-85 B
692 70-74 C
693 0-69 F
694
695 Generate the shell script that will send the mail out:
696
697 cat DATA/grades | dbformmail test1.txt > test1.sh
698
699 And run it:
700
701 sh <test1.sh
702
703 The last two steps can be combined:
704
705 cat DATA/grades | dbformmail test1.txt | sh
706
707 but I like to keep a copy of exactly what I send.
708
709 At the end of the semester you'll want to compute grade totals and
710 assign letter grades. Both fall out of dbroweval. For example, to
711 compute weighted total grades with a 40% midterm/60% final where the
712 midterm is 84 possible points and the final 100:
713
714 dbcol -rv total |
715 dbcolcreate total - |
716 dbroweval '
717 _total = .40 * _midterm/84.0 + .60 * _final/100.0;
718 _total = sprintf("%4.2f", _total);
719 if (_final eq "-" || ( _name =~ /^_/)) { _total = "-"; };' |
720 dbcolneaten
721
722 If you got the data originally from a spreadsheet, save it in "tab-
723 delimited" format and convert it with tabdelim_to_db (run
724 tabdelim_to_db -? for examples).
725
727 To convert the Unix password file to db:
728
729 cat /etc/passwd | sed 's/:/ /g'| \
730 dbcoldefine -F S login password uid gid gecos home shell \
731 >passwd.fsdb
732
733 To convert the group file
734
735 cat /etc/group | sed 's/:/ /g' | \
736 dbcoldefine -F S group password gid members \
737 >group.fsdb
738
739 To show the names of the groups that div7-members are in (assuming DIV7
740 is in the gecos field):
741
742 cat passwd.fsdb | dbrow '_gecos =~ /DIV7/' | dbcol login gid | \
743 dbjoin -i - -i group.fsdb gid | dbcol login group
744
746 Which Fsdb programs are the most complicated (based on number of test
747 cases)?
748
749 ls TEST/*.cmd | \
750 dbcoldefine test | \
751 dbroweval '_test =~ s@^TEST/([^_]+).*$@$1@' | \
752 dbrowuniq -c | \
753 dbsort -nr count | \
754 dbcolneaten
755
756 (Answer: dbmapreduce, then dbcolstats, dbfilealter and dbjoin.)
757
758 Stats on an exam (in $FILE, where $COLUMN is the name of the exam)?
759
760 cat $FILE | dbcolstats -q 4 $COLUMN <$FILE | dblistize | dbstripcomments
761
762 cat $FILE | dbcolhisto -g -n 20 $COLUMN | dbcolneaten | dbstripcomments
763
764 Merging a the hw1 column from file hw1.fsdb into grades.fsdb assuming
765 there's a common student id in column "id":
766
767 dbcol id hw1 <hw1.fsdb >t.fsdb
768
769 dbjoin -a -e - grades.fsdb t.fsdb id | \
770 dbsort name | \
771 dbcolneaten >new_grades.fsdb
772
773 Merging two fsdb files with the same rows:
774
775 cat file1.fsdb file2.fsdb >output.fsdb
776
777 or if you want to clean things up a bit
778
779 cat file1.fsdb file2.fsdb | dbstripextraheaders >output.fsdb
780
781 or if you want to know where the data came from
782
783 for i in 1 2
784 do
785 dbcolcreate source $i < file$i.fsdb
786 done >output.fsdb
787
788 (assumes you're using a Bourne-shell compatible shell, not csh).
789
791 As with any tool, one should (which means must) understand the limits
792 of the tool.
793
794 All Fsdb tools should run in constant memory. In some cases (such as
795 dbcolstats with quartiles, where the whole input must be re-read),
796 programs will spool data to disk if necessary.
797
798 Most tools buffer one or a few lines of data, so memory will scale with
799 the size of each line. (So lines with many columns, or when columns
800 have lots data, may cause large memory consumption.)
801
802 All Fsdb tools should run in constant or at worst "n log n" time.
803
804 All Fsdb tools use normal Perl math routines for computation. Although
805 I make every attempt to choose numerically stable algorithms (although
806 I also welcome feedback and suggestions for improvement), normal
807 rounding due to computer floating point approximations can result in
808 inaccuracies when data spans a large range of precision. (See for
809 example the dbcolstats_extrema test cases.)
810
811 Any requirements and limitations of each Fsdb tool is documented on its
812 manual page.
813
814 If any Fsdb program violates these assumptions, that is a bug that
815 should be documented on the tool's manual page or ideally fixed.
816
817 Fsdb does depend on Perl's correctness, and Perl (and Fsdb) have some
818 bugs. Fsdb should work on perl from version 5.10 onward.
819
821 There have been three versions of Fsdb; fsdb 1.0 is a complete re-write
822 of the pre-1995 versions, and was distributed from 1995 to 2007. Fsdb
823 2.0 is a significant re-write of the 1.x versions for reasons described
824 below.
825
826 Fsdb (in its various forms) has been used extensively by its author
827 since 1991. Since 1995 it's been used by two other researchers at UCLA
828 and several at ISI. In February 1998 it was announced to the Internet.
829 Since then it has found a few users, some outside where I work.
830
831 Major changes:
832
833 1.0 1997-07-22: first public release.
834 2.0 2008-01-25: rewrite to use a common library, and starting to use
835 threads.
836 2.12 2008-10-16: completion of the rewrite, and first RPM package.
837 2.44 2013-10-02: abandoning threads for improved performance
838
839 Fsdb 2.0 Rationale
840 I've thought about fsdb-2.0 for many years, but it was started in
841 earnest in 2007. Fsdb-2.0 has the following goals:
842
843 in-one-process processing
844 While fsdb is great on the Unix command line as a pipeline between
845 programs, it should also be possible to set it up to run in a
846 single process. And if it does so, it should be able to avoid
847 serializing and deserializing (converting to and from text) data
848 between each module. (Accomplished in fsdb-2.0: see dbpipeline,
849 although still needs tuning.)
850
851 clean IO API
852 Fsdb's roots go back to perl4 and 1991, so the fsdb-1.x library is
853 very, very crufty. More than just being ugly (but it was that
854 too), this made things reading from one format file and writing to
855 another the application's job, when it should be the library's.
856 (Accomplished in fsdb-1.15 and improved in 2.0: see Fsdb::IO.)
857
858 normalized module APIs
859 Because fsdb modules were added as needed over 10 years, sometimes
860 the module APIs became inconsistent. (For example, the 1.x
861 "dbcolcreate" required an empty value following the name of the new
862 column, but other programs specify empty values with the "-e"
863 argument.) We should smooth over these inconsistencies.
864 (Accomplished as each module was ported in 2.0 through 2.7.)
865
866 everyone handles all input formats
867 Given a clean IO API, the distinction between "colized" and
868 "listized" fsdb files should go away. Any program should be able
869 to read and write files in any format. (Accomplished in fsdb-2.1.)
870
871 Fsdb-2.0 preserves backwards compatibility where possible, but breaks
872 it where necessary to accomplish the above goals. In August 2008,
873 Fsdb-2.7 was declared preferred over the 1.x versions. Benchmarking in
874 2013 showed that threading performed much worse than just using pipes,
875 so Fsdb-2.44 uses threading "style", but implemented with processes
876 (via my "Freds" library).
877
878 Contributors
879 Fsdb includes code ported from Geoff Kuenning
880 ("Fsdb::Support::TDistribution").
881
882 Fsdb contributors: Ashvin Goel goel@cse.oge.edu, Geoff Kuenning
883 geoff@fmg.cs.ucla.edu, Vikram Visweswariah visweswa@isi.edu, Kannan
884 Varadahan kannan@isi.edu, Lars Eggert larse@isi.edu, Arkadi Gelfond
885 arkadig@dyna.com, David Graff graff@ldc.upenn.edu, Haobo Yu
886 haoboy@packetdesign.com, Pavlin Radoslavov pavlin@catarina.usc.edu,
887 Graham Phillips, Yuri Pradkin, Alefiya Hussain, Ya Xu, Michael
888 Schwendt, Fabio Silva fabio@isi.edu, Jerry Zhao zhaoy@isi.edu, Ning Xu
889 nxu@aludra.usc.edu, Martin Lukac mlukac@lecs.cs.ucla.edu, Xue Cai,
890 Michael McQuaid, Christopher Meng, Calvin Ardi, H. Merijn Brand, Lan
891 Wei, Hang Guo.
892
893 Fsdb includes datasets contributed from NIST (DATA/nist_zarr13.fsdb),
894 from
895 <http://www.itl.nist.gov/div898/handbook/eda/section4/eda4281.htm>, the
896 NIST/SEMATECH e-Handbook of Statistical Methods, section 1.4.2.8.1.
897 Background and Data. The source is public domain, and reproduced with
898 permission.
899
901 As stated in the introduction, Fsdb is an incompatible reimplementation
902 of the ideas found in "/rdb". By storing data in simple text files and
903 processing it with pipelines it is easy to experiment (in the shell)
904 and look at the output. The original implementation of this idea was
905 /rdb, a commercial product described in the book UNIX relational
906 database management: application development in the UNIX environment by
907 Rod Manis, Evan Schaffer, and Robert Jorgensen (and also at the web
908 page <http://www.rdb.com/>).
909
910 While Fsdb is inspired by Rdb, it includes no code from it, and Fsdb
911 makes several different design choices. In particular: rdb attempts to
912 be closer to a "real" database, with provision for locking, file
913 indexing. Fsdb focuses on single user use and so eschews these
914 choices. Rdb also has some support for interactive editing. Fsdb
915 leaves editing to text editors like emacs or vi.
916
917 In August, 2002 I found out Carlo Strozzi extended RDB with his package
918 NoSQL <http://www.linux.it/~carlos/nosql/>. According to Mr. Strozzi,
919 he implemented NoSQL in awk to avoid the Perl start-up of RDB.
920 Although I haven't found Perl startup overhead to be a big problem on
921 my platforms (from old Sparcstation IPCs to 2GHz Pentium-4s), you may
922 want to evaluate his system. The Linux Journal has a description of
923 NoSQL at <http://www.linuxjournal.com/article/3294>. It seems quite
924 similar to Fsdb. Like /rdb, NoSQL supports indexing (not present in
925 Fsdb). Fsdb appears to have richer support for statistics, and, as of
926 Fsdb-2.x, its support for Perl threading may support faster performance
927 (one-process, less serialization and deserialization).
928
930 Versions prior to 1.0 were released informally on my web page but were
931 not announced.
932
933 0.0 1991
934 started for my own research use
935
936 0.1 26-May-94
937 first check-in to RCS
938
939 0.2 15-Mar-95
940 parts now require perl5
941
942 1.0, 22-Jul-97
943 adds autoconf support and a test script.
944
945 1.1, 20-Jan-98
946 support for double space field separators, better tests
947
948 1.2, 11-Feb-98
949 minor changes and release on comp.lang.perl.announce
950
951 1.3, 17-Mar-98
952 · adds median and quartile options to dbstats
953
954 · adds dmalloc_to_db converter
955
956 · fixes some warnings
957
958 · dbjoin now can run on unsorted input
959
960 · fixes a dbjoin bug
961
962 · some more tests in the test suite
963
964 1.4, 27-Mar-98
965 · improves error messages (all should now report the program that
966 makes the error)
967
968 · fixed a bug in dbstats output when the mean is zero
969
970 1.5, 25-Jun-98
971 BUG FIX dbcolhisto, dbcolpercentile now handles non-numeric values like
972 dbstats
973 NEW dbcolstats computes zscores and tscores over a column
974 NEW dbcolscorrelate computes correlation coefficients between two
975 columns
976 INTERNAL ficus_getopt.pl has been replaced by DbGetopt.pm
977 BUG FIX all tests are now ``portable'' (previously some tests ran only
978 on my system)
979 BUG FIX you no longer need to have the db programs in your path (fix
980 arose from a discussion with Arkadi Gelfond)
981 BUG FIX installation no longer uses cp -f (to work on SunOS 4)
982
983 1.6, 24-May-99
984 NEW dbsort, dbstats, dbmultistats now run in constant memory (using tmp
985 files if necessary)
986 NEW dbcolmovingstats does moving means over a series of data
987 NEW dbcol has a -v option to get all columns except those listed
988 NEW dbmultistats does quartiles and medians
989 NEW dbstripextraheaders now also cleans up bogus comments before the
990 fist header
991 BUG FIX dbcolneaten works better with double-space-separated data
992
993 1.7, 5-Jan-00
994 NEW dbcolize now detects and rejects lines that contain embedded copies
995 of the field separator
996 NEW configure tries harder to prevent people from improperly
997 configuring/installing fsdb
998 NEW tcpdump_to_db converter (incomplete)
999 NEW tabdelim_to_db converter: from spreadsheet tab-delimited files to
1000 db
1001 NEW mailing lists for fsdb are "fsdb-announce@heidemann.la.ca.us"
1002 and "fsdb-talk@heidemann.la.ca.us"
1003 To subscribe to either, send mail
1004 to "fsdb-announce-request@heidemann.la.ca.us" or
1005 "fsdb-talk-request@heidemann.la.ca.us" with "subscribe" in the
1006 BODY of the message.
1007
1008 BUG FIX dbjoin used to produce incorrect output if there were extra,
1009 unmatched values in the 2nd table. Thanks to Graham Phillips for
1010 providing a test case.
1011 BUG FIX the sample commands in the usage strings now all should
1012 explicitly include the source of data (typically from "cat foo.fsdb
1013 |"). Thanks to Ya Xu for pointing out this documentation deficiency.
1014 BUG FIX (DOCUMENTATION) dbcolmovingstats had incorrect sample output.
1015
1016 1.8, 28-Jun-00
1017 BUG FIX header options are now preserved when writing with dblistize
1018 NEW dbrowuniq now optionally checks for uniqueness only on certain
1019 fields
1020 NEW dbrowsplituniq makes one pass through a file and splits it into
1021 separate files based on the given fields
1022 NEW converter for "crl" format network traces
1023 NEW anywhere you use arbitrary code (like dbroweval), _last_foo now
1024 maps to the last row's value for field _foo.
1025 OPTIMIZATION comment processing slightly changed so that dbmultistats
1026 now is much faster on files with lots of comments (for example, ~100k
1027 lines of comments and 700 lines of data!) (Thanks to Graham Phillips
1028 for pointing out this performance problem.)
1029 BUG FIX dbstats with median/quartiles now correctly handles singleton
1030 data points.
1031
1032 1.9, 6-Nov-00
1033 NEW dbfilesplit, split a single input file into multiple output files
1034 (based on code contributed by Pavlin Radoslavov).
1035 BUG FIX dbsort now works with perl-5.6
1036
1037 1.10, 10-Apr-01
1038 BUG FIX dbstats now handles the case where there are more n-tiles than
1039 data
1040 NEW dbstats now includes a -S option to optimize work on pre-sorted
1041 data (inspired by code contributed by Haobo Yu)
1042 BUG FIX dbsort now has a better estimate of memory usage when run on
1043 data with very short records (problem detected by Haobo Yu)
1044 BUG FIX cleanup of temporary files is slightly better
1045
1046 1.11, 2-Nov-01
1047 BUG FIX dbcolneaten now runs in constant memory
1048 NEW dbcolneaten now supports "field specifiers" that allow some control
1049 over how wide columns should be
1050 OPTIMIZATION dbsort now tries hard to be filesystem cache-friendly
1051 (inspired by "Information and Control in Gray-box Systems" by the
1052 Arpaci-Dusseau's at SOSP 2001)
1053 INTERNAL t_distr now ported to perl5 module DbTDistr
1054
1055 1.12, 30-Oct-02
1056 BUG FIX dbmultistats documentation typo fixed
1057 NEW dbcolmultiscale
1058 NEW dbcol has -r option for "relaxed error checking"
1059 NEW dbcolneaten has new -e option to strip end-of-line spaces
1060 NEW dbrow finally has a -v option to negate the test
1061 BUG FIX math bug in dbcoldiff fixed by Ashvin Goel (need to check
1062 Scheaffer test cases)
1063 BUG FIX some patches to run with Perl 5.8. Note: some programs
1064 (dbcolmultiscale, dbmultistats, dbrowsplituniq) generate warnings like:
1065 "Use of uninitialized value in concatenation (.)" or "string at
1066 /usr/lib/perl5/5.8.0/FileCache.pm line 98, <STDIN> line 2". Please
1067 ignore this until I figure out how to suppress it. (Thanks to Jerry
1068 Zhao for noticing perl-5.8 problems.)
1069 BUG FIX fixed an autoconf problem where configure would fail to find a
1070 reasonable prefix (thanks to Fabio Silva for reporting the problem)
1071 NEW db_to_html_table: simple conversion to html tables (NO fancy stuff)
1072 NEW dblib now has a function dblib_text2html() that will do simple
1073 conversion of iso-8859-1 to HTML
1074
1075 1.13, 4-Feb-04
1076 NEW fsdb added to the freebsd ports tree
1077 <http://www.freshports.org/databases/fsdb/>. Maintainer:
1078 "larse@isi.edu"
1079 BUG FIX properly handle trailing spaces when data must be numeric (ex.
1080 dbstats with -FS, see test dbstats_trailing_spaces). Fix from Ning Xu
1081 "nxu@aludra.usc.edu".
1082 NEW dbcolize error message improved (bug report from Terrence Brannon),
1083 and list format documented in the README.
1084 NEW cgi_to_db converts CGI.pm-format storage to fsdb list format
1085 BUG FIX handle numeric synonyms for column names in dbcol properly
1086 ENHANCEMENT "talking about columns" section added to README. Lack of
1087 documentation pointed out by Lars Eggert.
1088 CHANGE dbformmail now defaults to using Mail ("Berkeley Mail") to send
1089 mail, rather than sendmail (sendmail is still an option, but mail
1090 doesn't require running as root)
1091 NEW on platforms that support it (i.e., with perl 5.8), fsdb works fine
1092 with unicode
1093 NEW dbfilevalidate: check a db file for some common errors
1094
1095 1.14, 24-Aug-06
1096 ENHANCEMENT README cleanup
1097 INCOMPATIBLE CHANGE dbcolsplit renamed dbcolsplittocols
1098 NEW dbcolsplittorows split one column into multiple rows
1099 NEW dbcolsregression compute linear regression and correlation for two
1100 columns
1101 ENHANCEMENT cvs_to_db: better error handling, normalize field names,
1102 skip blank lines
1103 ENHANCEMENT dbjoin now detects (and fails) if non-joined files have
1104 duplicate names
1105 BUG FIX minor bug fixed in calculation of Student t-distributions
1106 (doesn't change any test output, but may have caused small errors)
1107
1108 1.15, 12-Nov-07
1109 NEW fsdb-1.14 added to the MacOS Fink system
1110 <http://pdb.finkproject.org/pdb/package.php/fsdb>. (Thanks to Lars
1111 Eggert for maintaining this port.)
1112 NEW Fsdb::IO::Reader and Fsdb::IO::Writer now provide reasonably clean
1113 OO I/O interfaces to Fsdb files. Highly recommended if you use fsdb
1114 directly from perl. In the fullness of time I expect to reimplement
1115 the entire thing using these APIs to replace the current dblib.pl which
1116 is still hobbled by its roots in perl4.
1117 NEW dbmapreduce now implements a Google-style map/reduce abstraction,
1118 generalizing dbmultistats.
1119 ENHANCEMENT fsdb now uses the Perl build system (Makefile.PL, etc.),
1120 instead of autoconf. This change paves the way to better perl-5-style
1121 modularization, proper manual pages, input of both listize and colize
1122 format for every program, and world peace.
1123 ENHANCEMENT dblib.pl is now moved to Fsdb::Old.pm.
1124 BUG FIX dbmultistats now propagates its format argument (-f). Bug and
1125 fix from Martin Lukac (thanks!).
1126 ENHANCEMENT dbformmail documentation now is clearer that it doesn't
1127 send the mail, you have to run the shell script it writes. (Problem
1128 observed by Unkyu Park.)
1129 ENHANCEMENT adapted to autoconf-2.61 (and then these changes were
1130 discarded in favor of The Perl Way.
1131 BUG FIX dbmultistats memory usage corrected (O(# tags), not O(1))
1132 ENHANCEMENT dbmultistats can now optionally run with pre-grouped input
1133 in O(1) memory
1134 ENHANCEMENT dbroweval -N was finally implemented (eat comments)
1135
1136 2.0, 25-Jan-08
1137 2.0, 25-Jan-08 --- a quiet 2.0 release (gearing up towards complete)
1138
1139 ENHANCEMENT: shifting old programs to Perl modules, with the front-end
1140 program as just a wrapper. In the short-term, this change just means
1141 programs have real man pages. In the long-run, it will mean that one
1142 can run a pipeline in a single Perl program. So far: dbcol, dbroweval,
1143 the new dbrowcount. dbsort the new dbmerge, the old "dbstats" (renamed
1144 dbcolstats), dbcolrename, dbcolcreate,
1145 NEW: Fsdb::Filter::dbpipeline is an internal-only module that lets one
1146 use fsdb commands from within perl (via threads).
1147 It also provides perl function aliases for the internal modules, so
1148 a string of fsdb commands in perl are nearly as terse as in the
1149 shell:
1150
1151 use Fsdb::Filter::dbpipeline qw(:all);
1152 dbpipeline(
1153 dbrow(qw(name test1)),
1154 dbroweval('_test1 += 5;')
1155 );
1156
1157 INCOMPATIBLE CHANGE: The old dbcolstats has been renamed
1158 dbcolstatscores. The new dbcolstats does the same thing as the old
1159 dbstats. This incompatibility is unfortunate but normalizes program
1160 names.
1161 CHANGE: The new dbcolstats program always outputs "-" (the default
1162 empty value) for statistics it cannot compute (for example, standard
1163 deviation if there is only one row), instead of the old mix of "-" and
1164 "na".
1165 INCOMPATIBLE CHANGE: The old dbcolstats program, now called
1166 dbcolstatscores, also has different arguments. The "-t mean,stddev"
1167 option is now "--tmean mean --tstddev stddev". See dbcolstatscores for
1168 details.
1169 INCOMPATIBLE CHANGE: dbcolcreate now assumes all new columns get the
1170 default value rather than requiring each column to have an initial
1171 constant value. To change the initial value, sue the new "-e" option.
1172 NEW: dbrowcount counts rows, an almost-subset of dbcolstats's "n"
1173 output (except without differentiating numeric/non-numeric input), or
1174 the equivalent of "dbstripcomments | wc -l".
1175 NEW: dbmerge merges two sorted files. This functionality was previously
1176 embedded in dbsort.
1177 INCOMPATIBLE CHANGE: dbjoin's "-i" option to include non-matches is now
1178 renamed "-a", so as to not conflict with the new standard option "-i"
1179 for input file.
1180
1181 2.1, 6-Apr-08
1182 2.1, 6-Apr-08 --- another alpha 2.0, but now all converted programs
1183 understand both listize and colize format
1184
1185 ENHANCEMENT: shifting more old programs to Perl modules. New in 2.1:
1186 dbcolneaten, dbcoldefine, dbcolhisto, dblistize, dbcolize, dbrecolize
1187 ENHANCEMENT dbmerge now handles an arbitrary number of input files, not
1188 just exactly two.
1189 NEW dbmerge2 is an internal routine that handles merging exactly two
1190 files.
1191 INCOMPATIBLE CHANGE dbjoin now specifies inputs like dbmerge2, rather
1192 than assuming the first two arguments were tables (as in fsdb-1).
1193 The old dbjoin argument "-i" is now "-a" or <--type=outer>.
1194
1195 A minor change: comments in the source files for dbjoin are now
1196 intermixed with output rather than being delayed until the end.
1197
1198 ENHANCEMENT dbsort now no longer produces warnings when null values are
1199 passed to numeric comparisons.
1200 BUG FIX dbroweval now once again works with code that lacks a trailing
1201 semicolon. (This bug fixes a regression from 1.15.)
1202 INCOMPATIBLE CHANGE dbcolneaten's old "-e" option (to avoid end-of-line
1203 spaces) is now "-E" to avoid conflicts with the standard empty field
1204 argument.
1205 INCOMPATIBLE CHANGE dbcolhisto's old "-e" option is now "-E" to avoid
1206 conflicts. And its "-n", "-s", and "-w" are now "-N", "-S", and "-W" to
1207 correspond.
1208 NEW dbfilealter replaces dbrecolize, dblistize, and dbcolize, but with
1209 different options.
1210 ENHANCEMENT The library routines "Fsdb::IO" now understand both list-
1211 format and column-format data, so all converted programs can now
1212 automatically read either format. This capability was one of the
1213 milestone goals for 2.0, so yea!
1214
1215 2.2, 23-May-08
1216 Release 2.2 is another 2.x alpha release. Now most of the commands are
1217 ported, but a few remain, and I plan one last incompatible change (to
1218 the file header) before 2.x final.
1219
1220 ENHANCEMENT
1221 shifting more old programs to Perl modules. New in 2.2:
1222 dbrowaccumulate, dbformmail. dbcolmovingstats. dbrowuniq.
1223 dbrowdiff. dbcolmerge. dbcolsplittocols. dbcolsplittorows.
1224 dbmapreduce. dbmultistats. dbrvstatdiff. Also dbrowenumerate
1225 exists only as a front-end (command-line) program.
1226
1227 INCOMPATIBLE CHANGE
1228 The following programs have been dropped from fsdb-2.x:
1229 dbcoltighten, dbfilesplit, dbstripextraheaders,
1230 dbstripleadingspace.
1231
1232 NEW combined_log_format_to_db to convert Apache logfiles
1233
1234 INCOMPATIBLE CHANGE
1235 Options to dbrowdiff are now -B and -I, not -a and -i.
1236
1237 INCOMPATIBLE CHANGE
1238 dbstripcomments is now dbfilestripcomments.
1239
1240 BUG FIXES
1241 dbcolneaten better handles empty columns; dbcolhisto warning
1242 suppressed (actually a bug in high-bucket handling).
1243
1244 INCOMPATIBLE CHANGE
1245 dbmultistats now requires a "-k" option in front of the key (tag)
1246 field, or if none is given, it will group by the first field (both
1247 like dbmapreduce).
1248
1249 KNOWN BUG
1250 dbmultistats with quantile option doesn't work currently.
1251
1252 INCOMPATIBLE CHANGE
1253 dbcoldiff is renamed dbrvstatdiff.
1254
1255 BUG FIXES
1256 dbformmail was leaving its log message as a command, not a
1257 comment. Oops. No longer.
1258
1259 2.3, 27-May-08 (alpha)
1260 Another alpha release, this one just to fix the critical dbjoin bug
1261 listed below (that happens to have blocked my MP3 jukebox :-).
1262
1263 BUG FIX
1264 Dbsort no longer hangs if given an input file with no rows.
1265
1266 BUG FIX
1267 Dbjoin now works with unsorted input coming from a pipeline (like
1268 stdin). Perl-5.8.8 has a bug (?) that was making this case
1269 fail---opening stdin in one thread, reading some, then reading more
1270 in a different thread caused an lseek which works on files, but
1271 fails on pipes like stdin. Go figure.
1272
1273 BUG FIX / KNOWN BUG
1274 The dbjoin fix also fixed dbmultistats -q (it now gives the right
1275 answer). Although a new bug appeared, messages like:
1276 Attempt to free unreferenced scalar: SV 0xa9dd0c4, Perl
1277 interpreter: 0xa8350b8 during global destruction. So the
1278 dbmultistats_quartile test is still disabled.
1279
1280 2.4, 18-Jun-08
1281 Another alpha release, mostly to fix minor usability problems in
1282 dbmapreduce and client functions.
1283
1284 ENHANCEMENT
1285 dbrow now defaults to running user supplied code without warnings
1286 (as with fsdb-1.x). Use "--warnings" or "-w" to turn them back on.
1287
1288 ENHANCEMENT
1289 dbroweval can now write different format output than the input,
1290 using the "-m" option.
1291
1292 KNOWN BUG
1293 dbmapreduce emits warnings on perl 5.10.0 about "Unbalanced string
1294 table refcount" and "Scalars leaked" when run with an external
1295 program as a reducer.
1296
1297 dbmultistats emits the warning "Attempt to free unreferenced
1298 scalar" when run with quartiles.
1299
1300 In each case the output is correct. I believe these can be
1301 ignored.
1302
1303 CHANGE
1304 dbmapreduce no longer logs a line for each reducer that is invoked.
1305
1306 2.5, 24-Jun-08
1307 Another alpha release, fixing more minor bugs in "dbmapreduce" and
1308 lossage in "Fsdb::IO".
1309
1310 ENHANCEMENT
1311 dbmapreduce can now tolerate non-map-aware reducers that pass back
1312 the key column in put. It also passes the current key as the last
1313 argument to external reducers.
1314
1315 BUG FIX
1316 Fsdb::IO::Reader, correctly handle "-header" option again. (Broken
1317 since fsdb-2.3.)
1318
1319 2.6, 11-Jul-08
1320 Another alpha release, needed to fix DaGronk. One new port, small bug
1321 fixes, and important fix to dbmapreduce.
1322
1323 ENHANCEMENT
1324 shifting more old programs to Perl modules. New in 2.2:
1325 dbcolpercentile.
1326
1327 INCOMPATIBLE CHANGE and ENHANCEMENTS dbcolpercentile arguments changed,
1328 use "--rank" to require ranking instead of "-r". Also, "--ascending"
1329 and "--descending" can now be specified separately, both for
1330 "--percentile" and "--rank".
1331 BUG FIX
1332 Sigh, the sense of the --warnings option in dbrow was inverted. No
1333 longer.
1334
1335 BUG FIX
1336 I found and fixed the string leaks (errors like "Unbalanced string
1337 table refcount" and "Scalars leaked") in dbmapreduce and
1338 dbmultistats. (All "IO::Handle"s in threads must be manually
1339 destroyed.)
1340
1341 BUG FIX
1342 The "-C" option to specify the column separator in dbcolsplittorows
1343 now works again (broken since it was ported).
1344
1345 2.7, 30-Jul-08 beta
1346
1347 The beta release of fsdb-2.x. Finally, all programs are ported. As
1348 statistics, the number of lines of non-library code doubled from 7.5k
1349 to 15.5k. The libraries are much more complete, going from 866 to 5164
1350 lines. The overall number of programs is about the same, although 19
1351 were dropped and 11 were added. The number of test cases has grown
1352 from 116 to 175. All programs are now in perl-5, no more shell scripts
1353 or perl-4. All programs now have manual pages.
1354
1355 Although this is a major step forward, I still expect to rename "fsdb"
1356 to "fsdb".
1357
1358 ENHANCEMENT
1359 shifting more old programs to Perl modules. New in 2.7:
1360 dbcolscorellate. dbcolsregression. cgi_to_db. dbfilevalidate.
1361 db_to_csv. csv_to_db, db_to_html_table, kitrace_to_db,
1362 tcpdump_to_db, tabdelim_to_db, ns_to_db.
1363
1364 INCOMPATIBLE CHANGE
1365 The following programs have been dropped from fsdb-2.x: db2dcliff,
1366 dbcolmultiscale, crl_to_db. ipchain_logs_to_db. They may come
1367 back, but seemed overly specialized. The following program
1368 dbrowsplituniq was dropped because it is superseded by dbmapreduce.
1369 dmalloc_to_db was dropped pending a test cases and examples.
1370
1371 ENHANCEMENT
1372 dbfilevalidate now has a "-c" option to correct errors.
1373
1374 NEW html_table_to_db provides the inverse of db_to_html_table.
1375
1376 2.8, 5-Aug-08
1377 Change header format, preserving forwards compatibility.
1378
1379 BUG FIX
1380 Complete editing pass over the manual, making sure it aligns with
1381 fsdb-2.x.
1382
1383 SEMI-COMPATIBLE CHANGE
1384 The header of fsdb files has changed, it is now #fsdb, not #h (or
1385 #L) and parsing of -F and -R are also different. See dbfilealter
1386 for the new specification. The v1 file format will be read,
1387 compatibly, but not written.
1388
1389 BUG FIX
1390 dbmapreduce now tolerates comments that precede the first key,
1391 instead of failing with an error message.
1392
1393 2.9, 6-Aug-08
1394 Still in beta; just a quick bug-fix for dbmapreduce.
1395
1396 ENHANCEMENT
1397 dbmapreduce now generates plausible output when given no rows of
1398 input.
1399
1400 2.10, 23-Sep-08
1401 Still in beta, but picking up some bug fixes.
1402
1403 ENHANCEMENT
1404 dbmapreduce now generates plausible output when given no rows of
1405 input.
1406
1407 ENHANCEMENT
1408 dbroweval the warnings option was backwards; now corrected. As a
1409 result, warnings in user code now default off (like in fsdb-1.x).
1410
1411 BUG FIX
1412 dbcolpercentile now defaults to assuming the target column is
1413 numeric. The new option "-N" allows selection of a non-numeric
1414 target.
1415
1416 BUG FIX
1417 dbcolscorrelate now includes "--sample" and "--nosample" options to
1418 compute the sample or full population correlation coefficients.
1419 Thanks to Xue Cai for finding this bug.
1420
1421 2.11, 14-Oct-08
1422 Still in beta, but picking up some bug fixes.
1423
1424 ENHANCEMENT
1425 html_table_to_db is now more aggressive about filling in empty
1426 cells with the official empty value, rather than leaving them blank
1427 or as whitespace.
1428
1429 ENHANCEMENT
1430 dbpipeline now catches failures during pipeline element setup and
1431 exits reasonably gracefully.
1432
1433 BUG FIX
1434 dbsubprocess now reaps child processes, thus avoiding running out
1435 of processes when used a lot.
1436
1437 2.12, 16-Oct-08
1438 Finally, a full (non-beta) 2.x release!
1439
1440 INCOMPATIBLE CHANGE
1441 Jdb has been renamed Fsdb, the flatfile-streaming database. This
1442 change affects all internal Perl APIs, but no shell command-level
1443 APIs. While Jdb served well for more than ten years, it is easily
1444 confused with the Java debugger (even though Jdb was there first!).
1445 It also is too generic to work well in web search engines.
1446 Finally, Jdb stands for ``John's database'', and we're a bit beyond
1447 that. (However, some call me the ``file-system guy'', so one could
1448 argue it retains that meeting.)
1449
1450 If you just used the shell commands, this change should not affect
1451 you. If you used the Perl-level libraries directly in your code,
1452 you should be able to rename "Jdb" to "Fsdb" to move to 2.12.
1453
1454 The jdb-announce list not yet been renamed, but it will be shortly.
1455
1456 With this release I've accomplished everything I wanted to in
1457 fsdb-2.x. I therefore expect to return to boring, bugfix releases.
1458
1459 2.13, 30-Oct-08
1460 BUG FIX
1461 dbrowaccumulate now treats non-numeric data as zero by default.
1462
1463 BUG FIX
1464 Fixed a perl-5.10ism in dbmapreduce that breaks that program under
1465 5.8. Thanks to Martin Lukac for reporting the bug.
1466
1467 2.14, 26-Nov-08
1468 BUG FIX
1469 Improved documentation for dbmapreduce's "-f" option.
1470
1471 ENHANCEMENT
1472 dbcolmovingstats how computes a moving standard deviation in
1473 addition to a moving mean.
1474
1475 2.15, 13-Apr-09
1476 BUG FIX
1477 Fix a make install bug reported by Shalindra Fernando.
1478
1479 2.16, 14-Apr-09
1480 BUG FIX
1481 Another minor release bug: on some systems programize_module looses
1482 executable permissions. Again reported by Shalindra Fernando.
1483
1484 2.17, 25-Jun-09
1485 TYPO FIXES
1486 Typo in the dbroweval manual fixed.
1487
1488 IMPROVEMENT
1489 There is no longer a comment line to label columns in dbcolneaten,
1490 instead the header line is tweaked to line up. This change
1491 restores the Jdb-1.x behavior, and means that repeated runs of
1492 dbcolneaten no longer add comment lines each time.
1493
1494 BUG FIX
1495 It turns out dbcolneaten was not correctly handling trailing
1496 spaces when given the "-E" option to suppress them. This
1497 regression is now fixed.
1498
1499 EXTENSION
1500 dbroweval(1) can now handle direct references to the last row via
1501 $lfref, a dubious but now documented feature.
1502
1503 BUG FIXES
1504 Separators set with "-C" in dbcolmerge and dbcolsplittocols were
1505 not properly setting the heading, and null fields were not
1506 recognized. The first bug was reported by Martin Lukac.
1507
1508 2.18, 1-Jul-09 A minor release
1509 IMPROVEMENT
1510 Documentation for Fsdb::IO::Reader has been improved.
1511
1512 IMPROVEMENT
1513 The package should now be PGP-signed.
1514
1515 2.19, 10-Jul-09
1516 BUG FIX
1517 Internal improvements to debugging output and robustness of
1518 dbmapreduce and dbpipeline. TEST/dbpipeline_first_fails.cmd re-
1519 enabled.
1520
1521 2.20, 30-Nov-09 (A collection of minor bugfixes, plus a build against
1522 Fedora 12.)
1523 BUG FIX
1524 Loging for dbmapreduce with code refs is now stable (it no longer
1525 includes a hex pointer to the code reference).
1526
1527 BUG FIX
1528 Better handling of mixed blank lines in Fsdb::IO::Reader (see test
1529 case dbcolize_blank_lines.cmd).
1530
1531 BUG FIX
1532 html_table_to_db now handles multi-line input better, and handles
1533 tables with COLSPAN.
1534
1535 BUG FIX
1536 dbpipeline now cleans up threads in an "eval" to prevent "cannot
1537 detach a joined thread" errors that popped up in perl-5.10.
1538 Hopefully this prevents a race condition that causes the test
1539 suites to hang about 20% of the time (in dbpipeline_first_fails).
1540
1541 IMPROVEMENT
1542 dbmapreduce now detects and correctly fails when the input and
1543 reducer have incompatible field separators.
1544
1545 IMPROVEMENT
1546 dbcolstats, dbcolhisto, dbcolscorrelate, dbcolsregression, and
1547 dbrowcount now all take an "-F" option to let one specify the
1548 output field separator (so they work better with dbmapreduce).
1549
1550 BUG FIX
1551 An omitted "-k" from the manual page of dbmultistats is now there.
1552 Bug reported by Unkyu Park.
1553
1554 2.21, 17-Apr-10 bug fix release
1555 BUG FIX
1556 Fsdb::IO::Writer now no longer fails with -outputheader => never
1557 (an obscure bug).
1558
1559 IMPROVEMENT
1560 Fsdb (in the warnings section) and dbcolstats now more carefully
1561 document how they handle (and do not handle) numerical precision
1562 problems, and other general limits. Thanks to Yuri Pradkin for
1563 prompting this documentation.
1564
1565 IMPROVEMENT
1566 "Fsdb::Support::fullname_to_sortkey" is now restored from "Jdb".
1567
1568 IMPROVEMENT
1569 Documention for multiple styles of input approaches (including
1570 performance description) added to Fsdb::IO.
1571
1572 2.22, 2010-10-31 One new tool dbcolcopylast and several bug fixes for Perl
1573 5.10.
1574 BUG FIX
1575 dbmerge now correctly handles n-way merges. Bug reported by Yuri
1576 Pradkin.
1577
1578 INCOMPARABLE CHANGE
1579 dbcolneaten now defaults to not padding the last column.
1580
1581 ADDITION
1582 dbrowenumerate now takes -N NewColumn to give the new column a name
1583 other than "count". Feature requested by Mike Rouch in January
1584 2005.
1585
1586 ADDITION
1587 New program dbcolcopylast copies the last value of a column into a
1588 new column copylast_column of the next row. New program requested
1589 by Fabio Silva; useful for converting dbmultistats output into
1590 dbrvstatdiff input.
1591
1592 BUG FIX
1593 Several tools (particularly dbmapreduce and dbmultistats) would
1594 report errors like "Unbalanced string table refcount: (1) for
1595 "STDOUT" during global destruction" on exit, at least on certain
1596 versions of Perl (for me on 5.10.1), but similar errors have been
1597 off-and-on for several Perl releases. Although I think my code
1598 looked OK, I worked around this problem with a different way of
1599 handling standard IO redirection.
1600
1601 2.23, 2011-03-10 Several small portability bugfixes; improved dbcolstats
1602 for large datasets
1603 IMPROVEMENT
1604 Documentation to dbrvstatdiff was changed to use "sd" to refer to
1605 standard deviation, not "ss" (which might be confused with sum-of-
1606 squares).
1607
1608 BUG FIX
1609 This documentation about dbmultistats was missing the -k option in
1610 some cases.
1611
1612 BUG FIX
1613 dbmapreduce was failing on MacOS-10.6.3 for some tests with the
1614 error
1615
1616 dbmapreduce: cannot run external dbmapreduce reduce program (perl TEST/dbmapreduce_external_with_key.pl)
1617
1618 The problem seemed to be only in the error, not in operation. On
1619 MacOS, the error is now suppressed. Thanks to Alefiya Hussain for
1620 providing access to a Mac system that allowed debugging of this
1621 problem.
1622
1623 IMPROVEMENT
1624 The csv_to_db command requires an external Perl library
1625 (Text::CSV_XS). On computers that lack this optional library,
1626 previously Fsdb would configure with a warning and then test cases
1627 would fail. Now those test cases are skipped with an additional
1628 warning.
1629
1630 BUG FIX
1631 The test suite now supports alternative valid output, as a hack to
1632 account for last-digit floating point differences. (Not very
1633 satisfying :-(
1634
1635 BUG FIX
1636 dbcolstats output for confidence intervals on very large datasets
1637 has changed. Previously it failed for more than 2^31-1 records,
1638 and handling of T-Distributions with thousands of rows was a bit
1639 dubious. Now datasets with more than 10000 are considered
1640 infinitely large and hopefully correctly handled.
1641
1642 2.24, 2011-04-15 Improvements to fix an old bug in dbmapreduce with
1643 different field separators
1644 IMPROVEMENT
1645 The dbfilealter command had a "--correct" option to work-around
1646 from incompatible field-separators, but it did nothing. Now it
1647 does the correct but sad, data-loosing thing.
1648
1649 IMPROVEMENT
1650 The dbmultistats command previously failed with an error message
1651 when invoked on input with a non-default field separator. The root
1652 cause was the underlying dbmapreduce that did not handle the case
1653 of reducers that generated output with a different field separator
1654 than the input. We now detect and repair incompatible field
1655 separators. This change corrects a problem originally documented
1656 and detected in Fsdb-2.20. Bug re-reported by Unkyu Park.
1657
1658 2.25, 2011-08-07 Two new tools, xml_to_db and dbfilepivot, and a bugfix for
1659 two people.
1660 IMPROVEMENT
1661 kitrace_to_db now supports a --utc option, which also fixes this
1662 test case for users outside of the Pacific time zone. Bug reported
1663 by David Graff, and also by Peter Desnoyers (within a week of each
1664 other :-)
1665
1666 NEW xml_to_db can convert simple, very regular XML files into Fsdb.
1667
1668 NEW dbfilepivot "pivots" a file, converting multiple rows corresponding
1669 to the same entity into a single row with multiple columns.
1670
1671 2.26, 2011-12-12 Bug fixes, particularly for perl-5.14.2.
1672 BUG FIX
1673 Bugs fixed in Fsdb::IO::Reader(3) manual page.
1674
1675 BUG FIX
1676 Fixed problems where dbcolstats was truncating floating point
1677 numbers when sorting. This strange behavior happens as of
1678 perl-5.14.2 and it seems like a Perl bug. I've worked around it
1679 for the test suites, but I'm a bit nervous.
1680
1681 2.27, 2012-11-15 Accumulated bug fixes.
1682 IMPROVEMENT
1683 csv_to_db now reports errors in CVS input with real diagnostics.
1684
1685 IMPROVEMENT
1686 dbcolmovingstats can now compute median, when given the "-m"
1687 option.
1688
1689 BUG FIX
1690 dbcolmovingstats non-numeric handling (the "-a" option) now works
1691 properly.
1692
1693 DOCUMENTATION
1694 The internal t/test_command.t test framework is now documented.
1695
1696 BUG FIX
1697 dbrowuniq now correctly handles the case where there is no input
1698 (previously it output a blank line, which is a malformed fsdb
1699 file). Thanks to Yuri Pradkin for reporting this bug.
1700
1701 2.28, 2012-11-15 A quick release to fix most rpmlint errors.
1702 BUG FIX
1703 Fixed a number of minor release problems (wrong permissions, old
1704 FSF address, etc.) found by rpmlint.
1705
1706 2.29, 2012-11-20 a quick release for CPAN testing
1707 IMPROVEMENT
1708 Tweaked the RPM spec.
1709
1710 IMPROVEMENT
1711 Modified Makefile.PL to fail gracefully on Perl installations that
1712 lack threads. (Without this fix, I get massive failures in the
1713 non-ithreads test system.)
1714
1715 2.30, 2012-11-25 improvements to perl portability
1716 BUG FIX
1717 Removed unicode character in documention of dbcolscorrelated so pod
1718 tests will pass. (Sigh, that should work :-( )
1719
1720 BUG FIX
1721 Fixed test suite failures on 5 tests (dbcolcreate_double_creation
1722 was the first) due to Carp's addition of a period. This problem
1723 was breaking Fsdb on perl-5.17. Thanks to Michael McQuaid for
1724 helping diagnose this problem.
1725
1726 IMPROVEMENT
1727 The test suite now prints out the names of tests it tries.
1728
1729 2.31, 2012-11-28 A release with actual improvements to dbfilepivot and
1730 dbrowuniq.
1731 BUG FIX
1732 Documentation fixes: typos in dbcolscorrelated, bugs in
1733 dbfilepivot, clarification for comment handling in
1734 Fsdb::IO::Reader.
1735
1736 IMPROVEMENT
1737 Previously dbfilepivot assumed the input was grouped by keys and
1738 didn't very that pre-condition. Now there is no pre-condition (it
1739 will sort the input by default), and it checks if the invariant is
1740 violated.
1741
1742 BUG FIX
1743 Previously dbfilepivot failed if the input had comments (oops :-);
1744 no longer.
1745
1746 IMPROVEMENT
1747 Now dbrowuniq has the "-L" option to preserve the last unique row
1748 (instead of the first), a common idiom.
1749
1750 2.32, 2012-12-21 Test suites should now be more numerically robust.
1751 NEW New dbfilediff does fsdb-aware file differencing. It does not do
1752 smart intuition of add/removes like Unix diff(1), but it does know
1753 about columns, and with "-E", it does numeric-aware differences.
1754
1755 IMPROVEMENT
1756 Test suites that are numeric now use dbfilediff to do numeric-aware
1757 comparisons, so the test suite should now be robust to slightly
1758 different computers and operating systems and compilers than
1759 exactly what I use.
1760
1761 2.33, 2012-12-23 Minor fixes to some test cases.
1762 IMPROVEMENT
1763 dbfilediff and dbrowuniq now supports the "-N" option to give the
1764 new column a different name. (And a test cases where this
1765 duplication mattered have been fixed.)
1766
1767 IMPROVEMENT
1768 dbrvstatdiff now show the t-test breakpoint with a reasonable
1769 number of floating point digits.
1770
1771 BUG FIX
1772 Fixed a numerical stability problem in the dbroweval_last test
1773 case.
1774
1776 2.34, 2013-02-10 Parallelism in dbmerge.
1777 IMPROVEMENT
1778 Documention for dbjoin now includes resource requirements.
1779
1780 IMPROVEMENT
1781 Default memory usage for dbsort is now about 256MB. (The world
1782 keeps moving forward.)
1783
1784 IMPROVEMENT
1785 dbmerge now does merging in parallel. As a side-effect, dbsort
1786 should be faster when input overflows memory. The level of
1787 parallelism can be limited with the "--parallelism" option. (There
1788 is more work to do here, but we're off to a start.)
1789
1790 2.35, 2013-02-23 Improvements to dbmerge parallelism
1791 BUG FIX
1792 Fsdb temporary files are now created more securely (with
1793 File::Temp).
1794
1795 IMPROVEMENT
1796 Programs that sort or merge on fields (dbmerge2, dbmerge, dbsort,
1797 dbjoin) now report an error if no fields on which to join or merge
1798 are given.
1799
1800 IMPROVEMENT
1801 Parallelism in dbmerge is should now be more consistent, with less
1802 starting and stopping.
1803
1804 IMPROVEMENT In dbmerge, the "--xargs" option lets one give input
1805 filenames on standard input, rather than the command line. This feature
1806 paves the way for faster dbsort for large inputs (by pipelining sorting
1807 and merging), expected in the next release.
1808
1809 2.36, 2013-02-25 dbsort pipelines with dbmerge
1810 IMPROVEMENT For large inputs, dbsort now pipelines sorting and merging,
1811 allowing earlier processing.
1812 BUG FIX Since 2.35, dbmerge delayed cleanup of intermediate files,
1813 thereby requiring extra disk space.
1814
1815 2.37, 2013-02-26 quick bugfix to support parallel sort and merge from
1816 recent releases
1817 BUG FIX Since 2.35, dbmerge delayed removal of input files given by
1818 "--xargs". This problem is now fixed.
1819
1820 2.38, 2013-04-29 minor bug fixes
1821 CLARIFICATION
1822 Configure now rejects Windows since tests seem to hang on some
1823 versions of Windows. (I would love help from a Windows developer
1824 to get this problem fixed, but I cannot do it.) See
1825 https://rt.cpan.org/Ticket/Display.html?id=84201.
1826
1827 IMPROVEMENT
1828 All programs that use temporary files (dbcolpercentile,
1829 dbcolscorrelate, dbcolstats, dbcolstatscores) now take the "-T"
1830 option and set the temporary directory consistently.
1831
1832 In addition, error messages are better when the temporary directory
1833 has problems. Problem reported by Liang Zhu.
1834
1835 BUG FIX
1836 dbmapreduce was failing with external, map-reduce aware reducers
1837 (when invoked with -M and an external program). (Sigh, did this
1838 case ever work?) This case should now work. Thanks to Yuri
1839 Pradkin for reporting this bug (in 2011).
1840
1841 BUG FIX
1842 Fixed perl-5.10 problem with dbmerge. Thanks to Yuri Pradkin for
1843 reporting this bug (in 2013).
1844
1845 2.39, date 2013-05-31 quick release for the dbrowuniq extension
1846 BUG FIX
1847 Actually in 2.38, the Fedora .spec got cleaner dependencies.
1848 Suggestion from Christopher Meng via
1849 <https://bugzilla.redhat.com/show_bug.cgi?id=877096>.
1850
1851 ENHANCEMENT
1852 Fsdb files are now explicitly set into UTF-8 encoding, unless one
1853 specifies "-encoding" to "Fsdb::IO".
1854
1855 ENHANCEMENT
1856 dbrowuniq now supports "-I" for incremental counting.
1857
1858 2.40, 2013-07-13 small bug fixes
1859 BUG FIX
1860 dbsort now has more respect for a user-given temporary directory;
1861 it no longer is ignored for merging.
1862
1863 IMPROVEMENT
1864 dbrowuniq now has options to output the first, last, and both first
1865 and last rows of a run ("-F", "-L", and "-B").
1866
1867 BUG FIX
1868 dbrowuniq now correctly handles "-N". Sigh, it didn't work before.
1869
1870 2.41, 2013-07-29 small bug and packaging fixes
1871 ENHANCEMENT
1872 Documentation to dbrvstatdiff improved (inspired by questions from
1873 Qian Kun).
1874
1875 BUG FIX
1876 dbrowuniq no longer duplicates singleton unique lines when
1877 outputting both (with "-B").
1878
1879 BUG FIX
1880 Add missing "XML::Simple" dependency to Makefile.PL.
1881
1882 ENHANCEMENT
1883 Tests now show the diff of the failing output if run with "make
1884 test TEST_VERBOSE=1".
1885
1886 ENHANCEMENT
1887 dbroweval now includes documentation for how to output extra rows.
1888 Suggestion from Yuri Pradkin.
1889
1890 BUG FIX
1891 Several improvements to the Fedora package from Michael Schwendt
1892 via <https://bugzilla.redhat.com/show_bug.cgi?id=877096>, and from
1893 the harsh master that is rpmlint. (I am stymied at teaching it
1894 that "outliers" is spelled correctly. Maybe I should send it
1895 Schneier's book. And an unresolvable invalid-spec-name lurks in
1896 the SRPM.)
1897
1898 2.42, 2013-07-31 A bug fix and packaging release.
1899 ENHANCEMENT
1900 Documentation to dbjoin improved to better memory usage. (Based on
1901 problem report by Lin Quan.)
1902
1903 BUG FIX
1904 The .spec is now perl-Fsdb.spec to satisfy rpmlint. Thanks to
1905 Christopher Meng for a specific bug report.
1906
1907 BUG FIX
1908 Test dbroweval_last.cmd no longer has a column that caused failures
1909 because of numerical instability.
1910
1911 BUG FIX
1912 Some tests now better handle bugs in old versions of perl (5.10,
1913 5.12). Thanks to Calvin Ardi for help debugging this on a Mac with
1914 perl-5.12, but the fix should affect other platforms.
1915
1916 2.43, 2013-08-27 Adds in-file compression.
1917 BUG FIX
1918 Changed the sort on TEST/dbsort_merge.cmd to strings (from
1919 numerics) so we're less susceptible to false test-failures due to
1920 floating point IO differences.
1921
1922 EXPERIMENTAL ENHANCEMENT
1923 Yet more parallelism in dbmerge: new "endgame-mode" builds a merge
1924 tree of processes at the end of large merge tasks to get maximally
1925 parallelism. Currently this feature is off by default because it
1926 can hang for some inputs. Enable this experimental feature with
1927 "--endgame".
1928
1929 ENHANCEMENT
1930 "Fsdb::IO" now handles being given "IO::Pipe" objects (as exercised
1931 by dbmerge).
1932
1933 BUG FIX
1934 Handling of NamedTmpfiles now supports concurrency. This fix will
1935 hopefully fix occasional "Use of uninitialized value $_ in string
1936 ne at ...NamedTmpfile.pm line 93." errors.
1937
1938 BUG FIX
1939 Fsdb now requires perl 5.10. This is a bug fix because some test
1940 cases used to require it, but this fact was not properly
1941 documented. (Back-porting to 5.008 would require removing all "//"
1942 operators.)
1943
1944 ENHANCEMENT
1945 Fsdb now handles automatic compression of file contents. Enable
1946 compression with "dbfilealter -Z xz" (or "gz" or "bz2"). All
1947 programs should operate on compressed files and leave the output
1948 with the same level of compression. "xz" is recommended as fastest
1949 and most efficient. "gz" is produces unrepeatable output (and so
1950 has no output test), it seems to insist on adding a timestamp.
1951
1952 2.44, 2013-10-02 A major change--all threads are gone.
1953 ENHANCEMENT
1954 Fsdb is now thread free and only uses processes for parallelism.
1955 This change is a big change--the entire motivation for Fsdb-2 was
1956 to exploit parallelism via threading. Parallelism--good, but perl
1957 threading--bad for performance. Horribly bad for performance.
1958 About 20x worse than pipes on my box. (See perl bug #119445 for
1959 the discussion.)
1960
1961 NEW "Fsdb::Support::Freds" provides a thread-like abstraction over
1962 forking, with some nice support for callbacks in the parent upon
1963 child termination.
1964
1965 ENHANCEMENT
1966 Details about removing threads: "dbpipeline" is thread free, and
1967 new tests to verify each of its parts. The easy cases are
1968 "dbcolpercentile", "dbcolstats", "dbfilepivot", "dbjoin", and
1969 "dbcolstatscores", each of which use it in simple ways
1970 (2013-09-09). "dbmerge" is now thread free (2013-09-13), but was a
1971 significant rewrite, which brought "dbsort" along. "dbmapreduce"
1972 is partly thread free (2013-09-21), again as a rewrite, and it
1973 brings "dbmultistats" along. Full "dbmapreduce" support took much
1974 longer (2013-10-02).
1975
1976 BUG FIX
1977 When running with user-only output ("-n"), dbroweval now resets the
1978 output vector $ofref after it has been output.
1979
1980 NEW dbcolcreate will create all columns at the head of each row with
1981 the "--first" option.
1982
1983 NEW dbfilecat will concatenate two files, verifying that they have the
1984 same schema.
1985
1986 ENHANCEMENT
1987 dbmapreduce now passes comments through, rather than eating them as
1988 before.
1989
1990 Also, dbmapreduce now supports a "--" option to prevent
1991 misinterpreting sub-program parameters as for dbmapreduce.
1992
1993 INCOMPATIBLE CHANGE
1994 dbmapreduce no longer figures out if it needs to add the key to the
1995 output. For multi-key-aware reducers, it never does (and cannot).
1996 For non-multi-key-aware reducers, it defaults to add the key and
1997 will now fail if the reducer adds the key (with error "dbcolcreate:
1998 attempt to create pre-existing column..."). In such cases, one
1999 must disable adding the key with the new option "--no-prepend-key".
2000
2001 INCOMPATIBLE CHANGE
2002 dbmapreduce no longer copies the input field separator by default.
2003 For multi-key-aware reducers, it never does (and cannot). For non-
2004 multi-key-aware reducers, it defaults to not copying the field
2005 separator, but it will copy it (the old default) with the
2006 "--copy-fs" option
2007
2008 2.45, 2013-10-07 cleanup from de-thread-ification
2009 BUG FIX
2010 Corrected a fast busy-wait in dbmerge.
2011
2012 ENHANCEMENT
2013 Endgame mode enabled in dbmerge; it (and also large cases of
2014 dbsort) should now exploit greater parallelism.
2015
2016 BUG FIX
2017 Test case with "Fsdb::BoundedQueue" (gone since 2.44) now removed.
2018
2019 2.46, 2013-10-08 continuing cleanup of our no-threads version
2020 BUG FIX
2021 Fixed some packaging details. (Really, threads are no longer
2022 required, missing tests in the MANIFEST.)
2023
2024 IMPROVEMENT
2025 dbsort now better communicates with the merge process to avoid
2026 bursty parallelism.
2027
2028 Fsdb::IO::Writer now can take "-autoflush =" 1> for line-buffered
2029 IO.
2030
2031 2.47, 2013-10-12 test suite cleanup for non-threaded perls
2032 BUG FIX
2033 Removed some stray "use threads" in some test cases. We didn't
2034 need them, and these were breaking non-threaded perls.
2035
2036 BUG FIX
2037 Better handling of Fred cleanup; should fix intermittent
2038 dbmapreduce failures on BSD.
2039
2040 ENHANCEMENT
2041 Improved test framework to show output when tests fail. (This
2042 time, for real.)
2043
2044 2.48, 2014-01-03 small bugfixes and improved release engineering
2045 ENHANCEMENT
2046 Test suites now skip tests for libraries that are missing. (Patch
2047 for missing "IO::Compresss:Xz" contributed by Calvin Ardi.)
2048
2049 ENHANCEMENT
2050 Removed references to Jdb in the package specification. Since the
2051 name was changed in 2008, there's no longer a huge need for
2052 backwards comparability. (Suggestion form Petr Šabata.)
2053
2054 ENHANCEMENT
2055 Test suites now invoke the perl using the path from
2056 $Config{perlpath}. Hopefully this helps testing in environments
2057 where there are multiple installed perls and the default perl is
2058 not the same as the perl-under-test (as happens in
2059 cpantesters.org).
2060
2061 BUG FIX
2062 Added specific encoding to this manpage to account for Unicode.
2063 Required to build correctly against perl-5.18.
2064
2065 2.49, 2014-01-04 bugfix to unicode handling in Fsdb IO (plus minor
2066 packaging fixes)
2067 BUG FIX
2068 Restored a line in the .spec to chmod g-s.
2069
2070 BUG FIX
2071 Unicode decoding is now handled correctly for programs that read
2072 from standard input. (Also: New test scripts cover unicode input
2073 and output.)
2074
2075 BUG FIX
2076 Fix to Fsdb documentation encoding line. Addresses test failure in
2077 perl-5.16 and earlier. (Who knew "encoding" had to be followed by
2078 a blank line.)
2079
2081 2.50, 2014-05-27 a quick release for spec tweaks
2082 ENHANCEMENT
2083 In dbroweval, the "-N" (no output, even comments) option now
2084 implies "-n", and it now suppresses the header and trailer.
2085
2086 BUG FIX
2087 A few more tweaks to the perl-Fsdb.spec from Petr Šabata.
2088
2089 BUG FIX
2090 Fixed 3 uses of "use v5.10" in test suites that were causing test
2091 failures (due to warnings, not real failures) on some platforms.
2092
2093 2.51, 2014-09-05 Feature enhancements to dbcolmovingstats, dbcolcreate,
2094 dbmapreduce, and new sqlselect_to_db
2095 ENHANCEMENT
2096 dbcolcreate now has a "--no-recreate-fatal" that causes it to
2097 ignore creation of existing columns (instead of failing).
2098
2099 ENHANCEMENT
2100 dbmapreduce once again is robust to reducers that output the key;
2101 "--no-prepend-key" is no longer mandatory.
2102
2103 ENHANCEMENT
2104 dbcolsplittorows can now enumerate the output rows with "-E".
2105
2106 BUG FIX
2107 dbcolmovingstats is more mathematically robust. Previously for
2108 some inputs and some platforms, floating point rounding could
2109 sometimes cause squareroots of negative numbers.
2110
2111 NEW sqlselect_to_db converts the output of the MySQL or MarinaDB select
2112 comment into fsdb format.
2113
2114 INCOMPATIBLE CHANGE
2115 dbfilediff now outputs the second row when doing sloppy numeric
2116 comparisons, to better support test suites.
2117
2118 2.52, 2014-11-03 Fixing the test suite for line number changes.
2119 ENHANCEMENT
2120 Test suites changes to be robust to exact line numbers of failures,
2121 since different Perl releases fail on different lines.
2122 <https://bugzilla.redhat.com/show_bug.cgi?id=1158380>
2123
2124 2.53, 2014-11-26 bug fixes and stability improvements to dbmapreduce
2125 ENHANCEMENT
2126 The dbfilediff how supports a "--quiet" option.
2127
2128 ENHANCEMENT
2129 Better documention of dbpipeline_filter.
2130
2131 BUGFIX
2132 Added groff-base and perl-podlators to the Fedora package spec.
2133 Fixes <https://bugzilla.redhat.com/show_bug.cgi?id=1163149>. (Also
2134 in package 2.52-2.)
2135
2136 BUGFIX
2137 An important stability improvement to dbmapreduce. It, plus
2138 dbmultistats, and dbcolstats now support controlled parallelism
2139 with the "--pararallelism=N" option. They default to run with the
2140 number of available CPUs. dbmapreduce also moderates its level of
2141 parallelism. Previously it would create reducers as needed,
2142 causing CPU thrashing if reducers ran much slower than data
2143 production.
2144
2145 BUGFIX
2146 The combination of dbmapreduce with dbrowenumerate now works as it
2147 should. (The obscure bug was an interaction with dbcolcreate with
2148 non-multi-key reducers that output their own key. dbmapreduce has
2149 too many useful corner cases.)
2150
2151 2.54, 2014-11-28 fix for the test suite to correct failing tests on not-my-
2152 platform
2153 BUGFIX
2154 Sigh, the test suite now has a test suite. Because, yes, I broke
2155 it, causing many incorrect failures at cpantesters. Now fixed.
2156
2157 2.55, 2015-01-05 many spelling fixes and dbcolmovingstats tests are more
2158 robust to different numeric precision
2159 ENHANCEMENT
2160 dbfilediff now can be extra quiet, as I continue to try to track
2161 down a numeric difference on FreeBSD AMD boxes.
2162
2163 ENHANCEMENT
2164 dbcolmovingstats gave different test output (just reflecting
2165 rounding error) when stddev approaches zero. We now detect hand
2166 handle this case. See
2167 <https://rt.cpan.org/Public/Bug/Display.html?id=101220> and thanks
2168 to H. Merijn Brand for the bug report.
2169
2170 BUG FIX
2171 Many, many spelling bugs found by H. Merijn Brand; thanks for the
2172 bug report.
2173
2174 INCOMPATBLE CHANGE
2175 A number of programs had misspelled "separator" in
2176 "--fieldseparator" and "--columnseparator" options as "seperator".
2177 These are now correctly spelled.
2178
2179 2.56, 2015-02-03 fix against Getopt::Long-2.43's stricter error checkign
2180 BUG FIX
2181 Internal argument parsing uses Getopt::Long, but mixed pass-through
2182 and <>. Bug reported by Petr Pisar at
2183 <https://bugzilla.redhat.com/show_bug.cgi?id=1188538>.a
2184
2185 BUG FIX
2186 Added missing BuildRequires for "XML::Simple".
2187
2188 2.57, 2015-04-29 Minor changes, with better performance from dbmulitstats.
2189 BUG FIX
2190 dbfilecat now honors "--remove-inputs" (previously it didn't).
2191 This omission meant that dbmapreduce (and dbmultistats) would
2192 accumulate files in /tmp when running. Bad news for inputs with 4M
2193 keys.
2194
2195 ENHANCMENT
2196 dbmultistats should be faster with lots of small keys. dbcolstats
2197 now supports "-k" to get some of the functionality of dbmultistats
2198 (if data is pre-sorted and median/quartiles are not required).
2199
2200 dbfilecat now honors "--remove-inputs" (previously it didn't).
2201 This omission meant that dbmapreduce (and dbmultistats) would
2202 accumulate files in /tmp when running. Bad news for inputs with 4M
2203 keys.
2204
2205 2.58, 2015-04-30 Bugfix in dbmerge
2206 BUG FIX
2207 Fixed a case where dbmerge suffered mojobake in endgame mode. This
2208 bug surfaced when dbsort was applied to large files (big enough to
2209 require merging) with unicode in them; the symptom was soemthing
2210 like:
2211 Wide character in print at /usr/lib64/perl5/IO/Handle.pm line
2212 420, <GEN12> line 111.
2213
2214 2.59, 2016-09-01 Collect a few small bug fixes and documentation
2215 improvements.
2216 BUG FIX
2217 More IO is explicitly marked UTF-8 to avoid Perl's tendency to
2218 mojibake on otherwise valid unicode input. This change helps
2219 html_table_to_db.
2220
2221 ENHANCEMENT
2222 dbcolscorrelate now crossreferences dbcolsregression.
2223
2224 ENHANCEMENT
2225 Documentation for dbrowdiff now clarifies that the default is
2226 baseline mode.
2227
2228 BUG FIX
2229 dbjoin now propagates "-T" into the sorting process (if it is
2230 required). Thanks to Lan Wei for reporting this bug.
2231
2232 2.60, 2016-09-04 Adds support for hash joins.
2233 ENHANCEMENT
2234 dbjoin now supports hash joins with "-t lefthash" and "-t
2235 righthash". Hash joins cache a table in memory, but do not require
2236 that the other table be sorted. They are ideal when joining a
2237 large table against a small one.
2238
2239 2.61, 2016-09-05 Support left and right outer joins.
2240 ENHANCEMENT
2241 dbjoin now handles left and right outer joins with "-t left" and
2242 "-t right".
2243
2244 ENHANCEMENT
2245 dbjoin hash joins are now selected with "-m lefthash" and "-m
2246 righthash" (not the shortlived "-t righthash" option).
2247 (Technically this change is incompatible with Fsdd-2.60, but no one
2248 but me ever used that version.)
2249
2250 2.62, 2016-11-29 A new yaml_to_db and other minor improvements.
2251 ENHANCEMENT
2252 Documentation for xml_to_db now includes sample output.
2253
2254 NEW yaml_to_db converts a specific form of YAML to fsdb.
2255
2256 BUG FIX
2257 The test suite now uses "diff -c -b" rather than "diff -cb" to make
2258 OpenBSD-5.9 happier, I hope.
2259
2260 ENHANCEMENT
2261 Comments that log operations at the end of each file now do simple
2262 quoting of spaces. (It is not guaranteed to be fully shell-
2263 compliant.)
2264
2265 ENHANCEMENT
2266 There is a new standard option, "--header", allowing one to specify
2267 an Fsdb header for inputs that lack it. Currently it is supported
2268 by dbcoldefine, dbrowuniq, dbmapreduce, dbmultistats, dbsort,
2269 dbpipeline.
2270
2271 ENHANCEMENT
2272 dbfilepivot now allows the --possible-pivots option, and if it is
2273 provided processes the data in one pass.
2274
2275 ENHANCEMENT
2276 dbroweval logs are now quoted.
2277
2278 2.63, 2017-02-03 Re-add some features supposedly in 2.62 but not, and add
2279 more --header options.
2280 ENHANCEMENT
2281 The option -j is now a synonym for --parallelism. (And several
2282 documention bugs about this option are fixed.)
2283
2284 ENHANCEMENT
2285 Additional support for "--header" in dbcolmerge, dbcol, dbrow, and
2286 dbroweval.
2287
2288 BUG FIX
2289 Version 2.62 was supposed to have this improvement, but did not
2290 (and now does): dbfilepivot now allows the --possible-pivots
2291 option, and if it is provided processes the data in one pass.
2292
2293 BUG FIX
2294 Version 2.62 was supposed to have this improvement, but did not
2295 (and now does): dbroweval logs are now quoted.
2296
2297 2.64, 2017-11-20 several small bugfixes and enhancements
2298 BUG FIX
2299 In dbroweval, the "next row" option previously did not correctly
2300 set up "_last_fieldname". It now does.
2301
2302 ENHANCEMENT
2303 The csv_to_db converter now has an optional "-F x" option to set
2304 the field separator.
2305
2306 ENHANCEMENT
2307 Finally dbcolsplittocols has a "--header" option, and a new "-N"
2308 option to give the list of resulting output columns.
2309
2310 INCOMPATIBLE CHANGE
2311 Now dbcolstats and dbmultistats produce no output (but a schema)
2312 when given no input but a schema. Previously they gave a null row
2313 of output. The "--output-on-no-input" and
2314 "--no-output-on-no-input" options can control this behavior.
2315
2316 2.65, 2018-02-16 Minor release, bug fix and -F option.
2317 ENHANCEMENT
2318 dbmultistats and dbmapreduce now both take a "-F x" option to set
2319 the field separator.
2320
2321 BUG FIX
2322 Fixed missing "use Carp" in dbcolstats. Also went back and cleaned
2323 up all uses of "croak()". Thanks to Zefram for the bug report.
2324
2326 John Heidemann, "johnh@isi.edu"
2327
2328 See "Contributors" for the many people who have contributed bug reports
2329 and fixes.
2330
2332 Fsdb is Copyright (C) 1991-2016 by John Heidemann <johnh@isi.edu>.
2333
2334 This program is free software; you can redistribute it and/or modify it
2335 under the terms of version 2 of the GNU General Public License as
2336 published by the Free Software Foundation.
2337
2338 This program is distributed in the hope that it will be useful, but
2339 WITHOUT ANY WARRANTY; without even the implied warranty of
2340 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
2341 General Public License for more details.
2342
2343 You should have received a copy of the GNU General Public License along
2344 with this program; if not, write to the Free Software Foundation, Inc.,
2345 675 Mass Ave, Cambridge, MA 02139, USA.
2346
2347 A copy of the GNU General Public License can be found in the file
2348 ``COPYING''.
2349
2351 Any comments about these programs should be sent to John Heidemann
2352 "johnh@isi.edu".
2353
2354
2355
2356perl v5.28.1 2018-12-21 Fsdb(3)