1MARIADB(1) MariaDB Database System MARIADB(1)
2
3
4
6 mariadb - the MariaDB command-line tool (mysql is now a symlink to
7 mariadb)
8
10 mysql [options] db_name
11
13 mysql is a simple SQL shell (with GNU readline capabilities). It
14 supports interactive and non-interactive use. When used interactively,
15 query results are presented in an ASCII-table format. When used
16 non-interactively (for example, as a filter), the result is presented
17 in tab-separated format. The output format can be changed using command
18 options.
19
20 If you have problems due to insufficient memory for large result sets,
21 use the --quick option. This forces mysql to retrieve results from the
22 server a row at a time rather than retrieving the entire result set and
23 buffering it in memory before displaying it. This is done by returning
24 the result set using the mysql_use_result() C API function in the
25 client/server library rather than mysql_store_result().
26
27 Using mysql is very easy. Invoke it from the prompt of your command
28 interpreter as follows:
29
30 shell> mysql db_name
31
32 Or:
33
34 shell> mysql --user=user_name --password=your_password db_name
35
36 Then type an SQL statement, end it with “;”, \g, or \G and press Enter.
37
38 Typing Control-C causes mysql to attempt to kill the current statement.
39 If this cannot be done, or Control-C is typed again before the
40 statement is killed, mysql exits.
41
42 You can execute SQL statements in a script file (batch file) like this:
43
44 shell> mysql db_name < script.sql > output.tab
45
47 mysql supports the following options, which can be specified on the
48 command line or in the [mysql], [client], [client-server] or [client-
49 mariadb] option file groups. mysql also supports the options for
50 processing option files.
51
52 • --help, -?, -I
53
54 Display a help message and exit.
55
56 • --abort-source-on-error
57
58 Abort 'source filename' operations in case of errors.
59
60 • --auto-rehash
61
62 Enable automatic rehashing. This option is on by default, which
63 enables database, table, and column name completion. Use
64 --disable-auto-rehash, --no-auto-rehash, or --skip-auto-rehash to
65 disable rehashing. That causes mysql to start faster, but you must
66 issue the rehash command if you want to use name completion.
67
68 To complete a name, enter the first part and press Tab. If the name
69 is unambiguous, mysql completes it. Otherwise, you can press Tab
70 again to see the possible names that begin with what you have typed
71 so far. Completion does not occur if there is no default database.
72
73 • --auto-vertical-output
74
75 Automatically switch to vertical output mode if the result is wider
76 than the terminal width.
77
78 • --batch, -B
79
80 Print results using tab as the column separator, with each row on a
81 new line. With this option, mysql does not use the history file.
82
83 Batch mode results in nontabular output format and escaping of
84 special characters. Escaping may be disabled by using raw mode; see
85 the description for the --raw option.
86
87 • --binary-mode
88
89 Binary mode allows certain character sequences to be processed as
90 data that would otherwise be treated with a special meaning by the
91 parser. Specifically, this switch turns off parsing of all client
92 commands except \C and DELIMITER in non-interactive mode (i.e.,
93 when binary mode is combined with either 1) piped input, 2) the
94 --batch mysql option, or 3) the 'source' command). Also, in binary
95 mode, occurrences of '\r\n' and ASCII '\0' are preserved within
96 strings, whereas by default, '\r\n' is translated to '\n' and '\0'
97 is disallowed in user input.
98
99 • --character-sets-dir=path
100
101 The directory where character sets are installed.
102
103 • --column-names
104
105 Write column names in results.
106
107 • --column-type-info, -m
108
109 Display result set metadata.
110
111 • --comments, -c
112
113 Whether to preserve comments in statements sent to the server. The
114 default is --skip-comments (discard comments), enable with
115 --comments (preserve comments).
116
117 • --compress, -C
118
119 Compress all information sent between the client and the server if
120 both support compression.
121
122 • --connect-timeout=seconds
123
124 Set the number of seconds before connection timeout. (Default value
125 is 0.)
126
127 • --database=db_name, -D db_name
128
129 The database to use.
130
131 • --debug[=debug_options], -# [debug_options]
132
133 Write a debugging log. A typical debug_options string is
134 ´d:t:o,file_name´. The default is ´d:t:o,/tmp/mysql.trace´.
135
136 • --debug-check
137
138 Print some debugging information when the program exits.
139
140 • --debug-info, -T
141
142 Prints debugging information and memory and CPU usage statistics
143 when the program exits.
144
145 • --default-auth=name
146
147 Default authentication client-side plugin to use.
148
149 • --default-character-set=charset_name
150
151 Use charset_name as the default character set for the client and
152 connection.
153
154 A common issue that can occur when the operating system uses utf8
155 or another multi-byte character set is that output from the mysql
156 client is formatted incorrectly, due to the fact that the MariaDB
157 client uses the latin1 character set by default. You can usually
158 fix such issues by using this option to force the client to use the
159 system character set instead.
160
161 • --defaults-extra-file=filename
162
163 Set filename as the file to read default options from after the
164 global defaults files has been read. Must be given as first
165 option.
166
167 • --defaults-file=filename
168
169 Set filename as the file to read default options from, override
170 global defaults files. Must be given as first option.
171
172 • --defaults-group-suffix=suffix
173
174 In addition to the groups named on the command line, read groups
175 that have the given suffix.
176
177 • --delimiter=str
178
179 Set the statement delimiter. The default is the semicolon character
180 (“;”).
181
182 • --disable-named-commands
183
184 Disable named commands. Use the \* form only, or use named commands
185 only at the beginning of a line ending with a semicolon (“;”).
186 mysql starts with this option enabled by default. However, even
187 with this option, long-format commands still work from the first
188 line. See the section called “MYSQL COMMANDS”.
189
190 • --enable-cleartext-plugin
191
192 Obsolete option. Exists only for MySQL compatibility.
193
194 • --execute=statement, -e statement
195
196 Execute the statement and quit. Disables --force and history file.
197 The default output format is like that produced with --batch.
198
199 • --force, -f
200
201 Continue even if an SQL error occurs. Sets --abort-source-on-error
202 to 0.
203
204 • --host=host_name, -h host_name
205
206 Connect to the MariaDB server on the given host.
207
208 • --html, -H
209
210 Produce HTML output.
211
212 • --ignore-spaces, -i
213
214 Ignore spaces after function names. Allows one to have spaces
215 (including tab characters and new line characters) between function
216 name and '('. The drawback is that this causes built in functions
217 to become reserved words.
218
219 • --init-command=str
220
221 SQL Command to execute when connecting to the MariaDB server. Will
222 automatically be re-executed when reconnecting.
223
224 • --line-numbers
225
226 Write line numbers for errors. Disable this with
227 --skip-line-numbers.
228
229 • --local-infile[={0|1}]
230
231 Enable or disable LOCAL capability for LOAD DATA INFILE. With no
232 value, the option enables LOCAL. The option may be given as
233 --local-infile=0 or --local-infile=1 to explicitly disable or
234 enable LOCAL. Enabling LOCAL has no effect if the server does not
235 also support it.
236
237 • --max-allowed-packet=num
238
239 Set the maximum packet length to send to or receive from the
240 server. (Default value is 16MB, largest 1GB.)
241
242 • --max-join-size=num
243
244 Set the automatic limit for rows in a join when using
245 --safe-updates. (Default value is 1,000,000.)
246
247 • --named-commands, -G
248
249 Enable named mysql commands. Long-format commands are allowed, not
250 just short-format commands. For example, quit and \q both are
251 recognized. Use --skip-named-commands to disable named commands.
252 See the section called “MYSQL COMMANDS”. Disabled by default.
253
254 •• --net-buffer-length=size
255
256 Set the buffer size for TCP/IP and socket communication. (Default
257 value is 16KB.)
258
259 • --no-auto-rehash, -A
260
261 This has the same effect as --skip-auto-rehash. See the description
262 for --auto-rehash.
263
264 • --no-beep, -b
265
266 Do not beep when errors occur.
267
268 • --no-defaults
269
270 Do not read default options from any option file. This must be
271 given as the first argument.
272
273 • --one-database, -o
274
275 Ignore statements except those those that occur while the default
276 database is the one named on the command line. This filtering is
277 limited, and based only on USE statements. This is useful for
278 skipping updates to other databases in the binary log.
279
280 • --pager[=command]
281
282 Use the given command for paging query output. If the command is
283 omitted, the default pager is the value of your PAGER environment
284 variable. Valid pagers are less, more, cat [> filename], and so
285 forth. This option works only on Unix and only in interactive mode.
286 To disable paging, use --skip-pager. the section called “MYSQL
287 COMMANDS”, discusses output paging further.
288
289 • --password[=password], -p[password]
290
291 The password to use when connecting to the server. If you use the
292 short option form (-p), you cannot have a space between the option
293 and the password. If you omit the password value following the
294 --password or -p option on the command line, mysql prompts for one.
295
296 Specifying a password on the command line should be considered
297 insecure. You can use an option file to avoid giving the password
298 on the command line.
299
300 • --pipe, -W
301
302 On Windows, connect to the server via a named pipe. This option
303 applies only if the server supports named-pipe connections.
304
305 • --plugin-dir=dir_name
306
307 Directory for client-side plugins.
308
309 • --port=port_num, -P port_num
310
311 The TCP/IP port number to use for the connection or 0 for default
312 to, in order of preference, my.cnf, $MYSQL_TCP_PORT, /etc/services,
313 built-in default (3306).
314
315 • --print-defaults
316
317 Print the program argument list and exit. This must be given as the
318 first argument.
319
320 • --progress-reports
321
322 Get progress reports for long running commands (such as ALTER
323 TABLE). (Defaults to on; use --skip-progress-reports to disable.)
324
325 • --prompt=format_str
326
327 Set the prompt to the specified format. The special sequences that
328 the prompt can contain are described in the section called “MYSQL
329 COMMANDS”.
330
331 • --protocol={TCP|SOCKET|PIPE|MEMORY}
332
333 The connection protocol to use for connecting to the server. It is
334 useful when the other connection parameters normally would cause a
335 protocol to be used other than the one you want.
336
337 • --quick, -q
338
339 Do not cache each query result, print each row as it is received.
340 This may slow down the server if the output is suspended. With this
341 option, mysql does not use the history file.
342
343 • --raw, -r
344
345 For tabular output, the “boxing” around columns enables one column
346 value to be distinguished from another. For nontabular output (such
347 as is produced in batch mode or when the --batch or --silent option
348 is given), special characters are escaped in the output so they can
349 be identified easily. Newline, tab, NUL, and backslash are written
350 as \n, \t, \0, and \\. The --raw option disables this character
351 escaping.
352
353 The following example demonstrates tabular versus nontabular output
354 and the use of raw mode to disable escaping:
355
356 % mysql
357 mysql> SELECT CHAR(92);
358 +----------+
359 | CHAR(92) |
360 +----------+
361 | \ |
362 +----------+
363 % mysql -s
364 mysql> SELECT CHAR(92);
365 CHAR(92)
366 \\
367 % mysql -s -r
368 mysql> SELECT CHAR(92);
369 CHAR(92)
370 \
371
372 • --reconnect
373
374 If the connection to the server is lost, automatically try to
375 reconnect. A single reconnect attempt is made each time the
376 connection is lost. Enabled by default, to disable use
377 --skip-reconnect or --disable-reconnect.
378
379 • --safe-updates, --i-am-a-dummy, -U
380
381 Allow only those UPDATE and DELETE statements that specify which
382 rows to modify by using key values. If you have set this option in
383 an option file, you can override it by using --safe-updates on the
384 command line. See the section called “MYSQL TIPS”, for more
385 information about this option.
386
387 • --secure-auth
388
389 Do not send passwords to the server in old (pre-4.1.1) format. This
390 prevents connections except for servers that use the newer password
391 format.
392
393 • --select-limit=limit
394
395 Set automatic limit for SELECT when using --safe-updates. (Default
396 value is 1,000.)
397
398 • --server-arg=name
399
400 Send name as a parameter to the embedded server.
401
402 • --show-warnings
403
404 Cause warnings to be shown after each statement if there are any.
405 This option applies to interactive and batch mode.
406
407 • --sigint-ignore
408
409 Ignore SIGINT signals (typically the result of typing Control-C).
410
411 • --silent, -s
412
413 Silent mode. Produce less output. This option can be given multiple
414 times to produce less and less output.
415
416 This option results in nontabular output format and escaping of
417 special characters. Escaping may be disabled by using raw mode; see
418 the description for the --raw option.
419
420 • --skip-auto-rehash
421
422 Disable automatic rehashing. Synonym for --disable-auto-rehash.
423
424 • --skip-column-names, -N
425
426 Do not write column names in results.
427
428 • --skip-line-numbers, -L
429
430 Do not write line numbers for errors. Useful when you want to
431 compare result files that include error messages.
432
433 • --socket=path, -S path
434
435 For connections to localhost, the Unix socket file to use, or, on
436 Windows, the name of the named pipe to use.
437
438 • --ssl
439
440 Enable SSL for connection (automatically enabled with other flags).
441 Disable with --skip-ssl.
442
443 • --ssl-ca=name
444
445 CA file in PEM format (check OpenSSL docs, implies --ssl).
446
447 • --ssl-capath=name
448
449 CA directory (check OpenSSL docs, implies --ssl).
450
451 • --ssl-cert=name
452
453 X509 cert in PEM format (check OpenSSL docs, implies --ssl).
454
455 • --ssl-cipher=name
456
457 SSL cipher to use (check OpenSSL docs, implies --ssl).
458
459 • --ssl-key=name
460
461 X509 key in PEM format (check OpenSSL docs, implies --ssl).
462
463 • --ssl-crl=name
464
465 Certificate revocation list (check OpenSSL docs, implies --ssl).
466
467 • --ssl-crlpath=name
468
469 Certificate revocation list path (check OpenSSL docs, implies
470 --ssl).
471
472 • --ssl-verify-server-cert
473
474 Verify server's "Common Name" in its cert against hostname used
475 when connecting. This option is disabled by default.
476
477 • --table, -t
478
479 Display output in table format. This is the default for interactive
480 use, but can be used to produce table output in batch mode.
481
482 • --tee=file_name
483
484 Append a copy of output to the given file. This option works only
485 in interactive mode. the section called “MYSQL COMMANDS”,
486 discusses tee files further.
487
488 • --unbuffered, -n
489
490 Flush the buffer after each query.
491
492 • --user=user_name, -u user_name
493
494 The MariaDB user name to use when connecting to the server.
495
496 • --verbose, -v
497
498 Verbose mode. Produce more output about what the program does. This
499 option can be given multiple times to produce more and more output.
500 (For example, -v -v -v produces table output format even in batch
501 mode.)
502
503 • --version, -V
504
505 Display version information and exit.
506
507 • --vertical, -E
508
509 Print query output rows vertically (one line per column value).
510 Without this option, you can specify vertical output for individual
511 statements by terminating them with \G.
512
513 • --wait, -w
514
515 If the connection cannot be established, wait and retry instead of
516 aborting.
517
518 • --xml, -X
519
520 Produce XML output. The output when --xml is used with mysql
521 matches that of mysqldump --xml. See mysqldump(1) for details.
522
523 The XML output also uses an XML namespace, as shown here:
524
525 shell> mysql --xml -uroot -e "SHOW VARIABLES LIKE ´version%´"
526 <?xml version="1.0"?>
527 <resultset statement="SHOW VARIABLES LIKE ´version%´" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
528 <row>
529 <field name="Variable_name">version</field>
530 <field name="Value">5.0.40-debug</field>
531 </row>
532 <row>
533 <field name="Variable_name">version_comment</field>
534 <field name="Value">Source distribution</field>
535 </row>
536 <row>
537 <field name="Variable_name">version_compile_machine</field>
538 <field name="Value">i686</field>
539 </row>
540 <row>
541 <field name="Variable_name">version_compile_os</field>
542 <field name="Value">suse-linux-gnu</field>
543 </row>
544 </resultset>
545
546 You can also set the following variables by using --var_name=value.
547
548 • connect_timeout
549
550 The number of seconds before connection timeout. (Default value
551 is 0.)
552
553 • max_allowed_packet
554
555 The maximum packet length to send to or receive from the
556 server. (Default value is 16MB.)
557
558 • max_join_size
559
560 The automatic limit for rows in a join when using
561 --safe-updates. (Default value is 1,000,000.)
562
563 • net_buffer_length
564
565 The buffer size for TCP/IP and socket communication. (Default
566 value is 16KB.)
567
568 • select_limit
569
570 The automatic limit for SELECT statements when using
571 --safe-updates. (Default value is 1,000.)
572
573 On Unix, the mysql client writes a record of executed statements to
574 a history file. By default, this file is named .mysql_history and
575 is created in your home directory. To specify a different file, set
576 the value of the MYSQL_HISTFILE environment variable.
577
578 The .mysql_history should be protected with a restrictive access
579 mode because sensitive information might be written to it, such as
580 the text of SQL statements that contain passwords.
581
582 If you do not want to maintain a history file, first remove
583 .mysql_history if it exists, and then use either of the following
584 techniques:
585
586 • Set the MYSQL_HISTFILE variable to /dev/null. To cause this
587 setting to take effect each time you log in, put the setting in
588 one of your shell´s startup files.
589
590 • Create .mysql_history as a symbolic link to /dev/null:
591
592 shell> ln -s /dev/null $HOME/.mysql_history
593
594 You need do this only once.
595
597 mysql sends each SQL statement that you issue to the server to be
598 executed. There is also a set of commands that mysql itself interprets.
599 For a list of these commands, type help or \h at the mysql> prompt:
600
601 mysql> help
602 List of all MySQL commands:
603 Note that all text commands must be first on line and end with ´;´
604 ? (\?) Synonym for `help´.
605 clear (\c) Clear command.
606 connect (\r) Reconnect to the server. Optional arguments are db and host.
607 delimiter (\d) Set statement delimiter.
608 edit (\e) Edit command with $EDITOR.
609 ego (\G) Send command to mysql server, display result vertically.
610 exit (\q) Exit mysql. Same as quit.
611 go (\g) Send command to mysql server.
612 help (\h) Display this help.
613 nopager (\n) Disable pager, print to stdout.
614 notee (\t) Don´t write into outfile.
615 pager (\P) Set PAGER [to_pager]. Print the query results via PAGER.
616 print (\p) Print current command.
617 prompt (\R) Change your mysql prompt.
618 quit (\q) Quit mysql.
619 rehash (\#) Rebuild completion hash.
620 source (\.) Execute an SQL script file. Takes a file name as an argument.
621 status (\s) Get status information from the server.
622 system (\!) Execute a system shell command.
623 tee (\T) Set outfile [to_outfile]. Append everything into given
624 outfile.
625 use (\u) Use another database. Takes database name as argument.
626 charset (\C) Switch to another charset. Might be needed for processing
627 binlog with multi-byte charsets.
628 warnings (\W) Show warnings after every statement.
629 nowarning (\w) Don´t show warnings after every statement.
630 For server side help, type ´help contents´
631
632 Each command has both a long and short form. The long form is not case
633 sensitive; the short form is. The long form can be followed by an
634 optional semicolon terminator, but the short form should not.
635
636 The use of short-form commands within multi-line /* ... */ comments is
637 not supported.
638
639 • help [arg], \h [arg], \? [arg], ? [arg]
640
641 Display a help message listing the available mysql commands.
642
643 If you provide an argument to the help command, mysql uses it as a
644 search string to access server-side help. For more information, see
645 the section called “MYSQL SERVER-SIDE HELP”.
646
647 • charset charset_name, \C charset_name
648
649 Change the default character set and issue a SET NAMES statement.
650 This enables the character set to remain synchronized on the client
651 and server if mysql is run with auto-reconnect enabled (which is
652 not recommended), because the specified character set is used for
653 reconnects.
654
655 • clear, \c
656
657 Clear the current input. Use this if you change your mind about
658 executing the statement that you are entering.
659
660 • connect [db_name host_name]], \r [db_name host_name]]
661
662 Reconnect to the server. The optional database name and host name
663 arguments may be given to specify the default database or the host
664 where the server is running. If omitted, the current values are
665 used.
666
667 • delimiter str, \d str
668
669 Change the string that mysql interprets as the separator between
670 SQL statements. The default is the semicolon character (“;”).
671
672 The delimiter can be specified as an unquoted or quoted argument.
673 Quoting can be done with either single quote (´) or douple quote
674 (") characters. To include a quote within a quoted string, either
675 quote the string with the other quote character or escape the quote
676 with a backslash (“\”) character. Backslash should be avoided
677 outside of quoted strings because it is the escape character for
678 MariaDB. For an unquoted argument, the delmiter is read up to the
679 first space or end of line. For a quoted argument, the delimiter is
680 read up to the matching quote on the line.
681
682 When the delimiter recognized by mysql is set to something other
683 than the default of “;”, instances of that character are sent to
684 the server without interpretation. However, the server itself still
685 interprets “;” as a statement delimiter and processes statements
686 accordingly. This behavior on the server side comes into play for
687 multiple-statement execution, and for parsing the body of stored
688 procedures and functions, triggers, and events.
689
690 • edit, \e
691
692 Edit the current input statement. mysql checks the values of the
693 EDITOR and VISUAL environment variables to determine which editor
694 to use. The default editor is vi if neither variable is set.
695
696 The edit command works only in Unix.
697
698 • ego, \G
699
700 Send the current statement to the server to be executed and display
701 the result using vertical format.
702
703 • exit, \q
704
705 Exit mysql.
706
707 • go, \g
708
709 Send the current statement to the server to be executed.
710
711 • nopager, \n
712
713 Disable output paging. See the description for pager.
714
715 The nopager command works only in Unix.
716
717 • notee, \t
718
719 Disable output copying to the tee file. See the description for
720 tee.
721
722 • nowarning, \w
723
724 Enable display of warnings after each statement.
725
726 • pager [command], \P [command]
727
728 Enable output paging. By using the --pager option when you invoke
729 mysql, it is possible to browse or search query results in
730 interactive mode with Unix programs such as less, more, or any
731 other similar program. If you specify no value for the option,
732 mysql checks the value of the PAGER environment variable and sets
733 the pager to that. Pager functionality works only in interactive
734 mode.
735
736 Output paging can be enabled interactively with the pager command
737 and disabled with nopager. The command takes an optional argument;
738 if given, the paging program is set to that. With no argument, the
739 pager is set to the pager that was set on the command line, or
740 stdout if no pager was specified.
741
742 Output paging works only in Unix because it uses the popen()
743 function, which does not exist on Windows. For Windows, the tee
744 option can be used instead to save query output, although it is not
745 as convenient as pager for browsing output in some situations.
746
747 • print, \p
748
749 Print the current input statement without executing it.
750
751 • prompt [str], \R [str]
752
753 Reconfigure the mysql prompt to the given string. The special
754 character sequences that can be used in the prompt are described
755 later in this section.
756
757 If you specify the prompt command with no argument, mysql resets
758 the prompt to the default of mysql>.
759
760 • quit, \q
761
762 Exit mysql.
763
764 • rehash, \#
765
766 Rebuild the completion hash that enables database, table, and
767 column name completion while you are entering statements. (See the
768 description for the --auto-rehash option.)
769
770 • source file_name, \. file_name
771
772 Read the named file and executes the statements contained therein.
773 On Windows, you can specify path name separators as / or \\.
774
775 • status, \s
776
777 Provide status information about the connection and the server you
778 are using. If you are running in --safe-updates mode, status also
779 prints the values for the mysql variables that affect your queries.
780
781 • system command, \! command
782
783 Execute the given command using your default command interpreter.
784
785 The system command works only in Unix.
786
787 • tee [file_name], \T [file_name]
788
789 By using the --tee option when you invoke mysql, you can log
790 statements and their output. All the data displayed on the screen
791 is appended into a given file. This can be very useful for
792 debugging purposes also. mysql flushes results to the file after
793 each statement, just before it prints its next prompt. Tee
794 functionality works only in interactive mode.
795
796 You can enable this feature interactively with the tee command.
797 Without a parameter, the previous file is used. The tee file can be
798 disabled with the notee command. Executing tee again re-enables
799 logging.
800
801 • use db_name, \u db_name
802
803 Use db_name as the default database.
804
805 • warnings, \W
806
807 Enable display of warnings after each statement (if there are any).
808
809 Here are a few tips about the pager command:
810
811 • You can use it to write to a file and the results go only to the
812 file:
813
814 mysql> pager cat > /tmp/log.txt
815
816 You can also pass any options for the program that you want to use
817 as your pager:
818
819 mysql> pager less -n -i -S
820
821 • In the preceding example, note the -S option. You may find it very
822 useful for browsing wide query results. Sometimes a very wide
823 result set is difficult to read on the screen. The -S option to
824 less can make the result set much more readable because you can
825 scroll it horizontally using the left-arrow and right-arrow keys.
826 You can also use -S interactively within less to switch the
827 horizontal-browse mode on and off. For more information, read the
828 less manual page:
829
830 shell> man less
831
832 • The -F and -X options may be used with less to cause it to exit if
833 output fits on one screen, which is convenient when no scrolling is
834 necessary:
835
836 mysql> pager less -n -i -S -F -X
837
838 • You can specify very complex pager commands for handling query
839 output:
840
841 mysql> pager cat | tee /dr1/tmp/res.txt \
842 | tee /dr2/tmp/res2.txt | less -n -i -S
843
844 In this example, the command would send query results to two files
845 in two different directories on two different file systems mounted
846 on /dr1 and /dr2, yet still display the results onscreen via less.
847
848 You can also combine the tee and pager functions. Have a tee file
849 enabled and pager set to less, and you are able to browse the results
850 using the less program and still have everything appended into a file
851 the same time. The difference between the Unix tee used with the pager
852 command and the mysql built-in tee command is that the built-in tee
853 works even if you do not have the Unix tee available. The built-in tee
854 also logs everything that is printed on the screen, whereas the Unix
855 tee used with pager does not log quite that much. Additionally, tee
856 file logging can be turned on and off interactively from within mysql.
857 This is useful when you want to log some queries to a file, but not
858 others.
859
860 The prompt command reconfigures the default mysql> prompt. The string
861 for defining the prompt can contain the following special sequences.
862
863 ┌───────┬────────────────────────────┐
864 │Option │ Description │
865 ├───────┼────────────────────────────┤
866 │\c │ A counter that increments │
867 │ │ for each statement you │
868 │ │ issue │
869 ├───────┼────────────────────────────┤
870 │\D │ The full current date │
871 ├───────┼────────────────────────────┤
872 │\d │ The default database │
873 ├───────┼────────────────────────────┤
874 │\h │ The server host │
875 ├───────┼────────────────────────────┤
876 │\l │ The current delimiter (new │
877 │ │ in 5.1.12) │
878 ├───────┼────────────────────────────┤
879 │\m │ Minutes of the current │
880 │ │ time │
881 ├───────┼────────────────────────────┤
882 │\n │ A newline character │
883 ├───────┼────────────────────────────┤
884 │\O │ The current month in │
885 │ │ three-letter format (Jan, │
886 │ │ Feb, ...) │
887 ├───────┼────────────────────────────┤
888 │\o │ The current month in │
889 │ │ numeric format │
890 ├───────┼────────────────────────────┤
891 │\P │ am/pm │
892 ├───────┼────────────────────────────┤
893 │\p │ The current TCP/IP port or │
894 │ │ socket file │
895 ├───────┼────────────────────────────┤
896 │\R │ The current time, in │
897 │ │ 24-hour military time │
898 │ │ (0–23) │
899 ├───────┼────────────────────────────┤
900 │\r │ The current time, standard │
901 │ │ 12-hour time (1–12) │
902 ├───────┼────────────────────────────┤
903 │\S │ Semicolon │
904 ├───────┼────────────────────────────┤
905 │\s │ Seconds of the current │
906 │ │ time │
907 ├───────┼────────────────────────────┤
908 │\t │ A tab character │
909 ├───────┼────────────────────────────┤
910 │\U │ │
911 │ │ Your full │
912 │ │ user_name@host_name │
913 │ │ account name │
914 ├───────┼────────────────────────────┤
915 │\u │ Your user name │
916 ├───────┼────────────────────────────┤
917 │\v │ The server version │
918 ├───────┼────────────────────────────┤
919 │\w │ The current day of the │
920 │ │ week in three-letter │
921 │ │ format (Mon, Tue, ...) │
922 ├───────┼────────────────────────────┤
923 │\Y │ The current year, four │
924 │ │ digits │
925 ├───────┼────────────────────────────┤
926 │\y │ The current year, two │
927 │ │ digits │
928 ├───────┼────────────────────────────┤
929 │\_ │ A space │
930 ├───────┼────────────────────────────┤
931 │\ │ A space (a space follows │
932 │ │ the backslash) │
933 ├───────┼────────────────────────────┤
934 │\´ │ Single quote │
935 ├───────┼────────────────────────────┤
936 │\" │ Double quote │
937 ├───────┼────────────────────────────┤
938 │\\ │ A literal “\” backslash │
939 │ │ character │
940 ├───────┼────────────────────────────┤
941 │\x │ │
942 │ │ x, for any “x” not │
943 │ │ listed above │
944 └───────┴────────────────────────────┘
945
946 You can set the prompt in several ways:
947
948 • Use an environment variable. You can set the MYSQL_PS1 environment
949 variable to a prompt string. For example:
950
951 shell> export MYSQL_PS1="(\u@\h) [\d]> "
952
953 • Use a command-line option. You can set the --prompt option on the
954 command line to mysql. For example:
955
956 shell> mysql --prompt="(\u@\h) [\d]> "
957 (user@host) [database]>
958
959 • Use an option file. You can set the prompt option in the [mysql]
960 group of any MariaDB option file, such as /etc/my.cnf or the
961 .my.cnf file in your home directory. For example:
962
963 [mysql]
964 prompt=(\\u@\\h) [\\d]>\\_
965
966 In this example, note that the backslashes are doubled. If you set
967 the prompt using the prompt option in an option file, it is
968 advisable to double the backslashes when using the special prompt
969 options. There is some overlap in the set of allowable prompt
970 options and the set of special escape sequences that are recognized
971 in option files. The overlap may cause you problems if you use
972 single backslashes. For example, \s is interpreted as a space
973 rather than as the current seconds value. The following example
974 shows how to define a prompt within an option file to include the
975 current time in HH:MM:SS> format:
976
977 [mysql]
978 prompt="\\r:\\m:\\s> "
979
980 • Set the prompt interactively. You can change your prompt
981 interactively by using the prompt (or \R) command. For example:
982
983 mysql> prompt (\u@\h) [\d]>\_
984 PROMPT set to ´(\u@\h) [\d]>\_´
985 (user@host) [database]>
986 (user@host) [database]> prompt
987 Returning to default PROMPT of mysql>
988 mysql>
989
991 mysql> help search_string
992
993 If you provide an argument to the help command, mysql uses it as a
994 search string to access server-side help. The proper operation of this
995 command requires that the help tables in the mysql database be
996 initialized with help topic information.
997
998 If there is no match for the search string, the search fails:
999
1000 mysql> help me
1001 Nothing found
1002 Please try to run ´help contents´ for a list of all accessible topics
1003
1004 Use help contents to see a list of the help categories:
1005
1006 mysql> help contents
1007 You asked for help about help category: "Contents"
1008 For more information, type ´help <item>´, where <item> is one of the
1009 following categories:
1010 Account Management
1011 Administration
1012 Data Definition
1013 Data Manipulation
1014 Data Types
1015 Functions
1016 Functions and Modifiers for Use with GROUP BY
1017 Geographic Features
1018 Language Structure
1019 Plugins
1020 Storage Engines
1021 Stored Routines
1022 Table Maintenance
1023 Transactions
1024 Triggers
1025
1026 If the search string matches multiple items, mysql shows a list of
1027 matching topics:
1028
1029 mysql> help logs
1030 Many help items for your request exist.
1031 To make a more specific request, please type ´help <item>´,
1032 where <item> is one of the following topics:
1033 SHOW
1034 SHOW BINARY LOGS
1035 SHOW ENGINE
1036 SHOW LOGS
1037
1038 Use a topic as the search string to see the help entry for that topic:
1039
1040 mysql> help show binary logs
1041 Name: ´SHOW BINARY LOGS´
1042 Description:
1043 Syntax:
1044 SHOW BINARY LOGS
1045 SHOW MASTER LOGS
1046 Lists the binary log files on the server. This statement is used as
1047 part of the procedure described in [purge-binary-logs], that shows how
1048 to determine which logs can be purged.
1049 mysql> SHOW BINARY LOGS;
1050 +---------------+-----------+
1051 | Log_name | File_size |
1052 +---------------+-----------+
1053 | binlog.000015 | 724935 |
1054 | binlog.000016 | 733481 |
1055 +---------------+-----------+
1056
1058 The mysql client typically is used interactively, like this:
1059
1060 shell> mysql db_name
1061
1062 However, it is also possible to put your SQL statements in a file and
1063 then tell mysql to read its input from that file. To do so, create a
1064 text file text_file that contains the statements you wish to execute.
1065 Then invoke mysql as shown here:
1066
1067 shell> mysql db_name < text_file
1068
1069 If you place a USE db_name statement as the first statement in the
1070 file, it is unnecessary to specify the database name on the command
1071 line:
1072
1073 shell> mysql < text_file
1074
1075 If you are already running mysql, you can execute an SQL script file
1076 using the source command or \. command:
1077
1078 mysql> source file_name
1079 mysql> \. file_name
1080
1081 Sometimes you may want your script to display progress information to
1082 the user. For this you can insert statements like this:
1083
1084 SELECT ´<info_to_display>´ AS ´ ´;
1085
1086 The statement shown outputs <info_to_display>.
1087
1088 You can also invoke mysql with the --verbose option, which causes each
1089 statement to be displayed before the result that it produces.
1090
1091 mysql ignores Unicode byte order mark (BOM) characters at the beginning
1092 of input files. Presence of a BOM does not cause mysql to change its
1093 default character set. To do that, invoke mysql with an option such as
1094 --default-character-set=utf8.
1095
1097 This section describes some techniques that can help you use mysql more
1098 effectively.
1099
1100 Displaying Query Results Vertically
1101 Some query results are much more readable when displayed vertically,
1102 instead of in the usual horizontal table format. Queries can be
1103 displayed vertically by terminating the query with \G instead of a
1104 semicolon. For example, longer text values that include newlines often
1105 are much easier to read with vertical output:
1106
1107 mysql> SELECT * FROM mails WHERE LENGTH(txt) < 300 LIMIT 300,1\G
1108 *************************** 1. row ***************************
1109 msg_nro: 3068
1110 date: 2000-03-01 23:29:50
1111 time_zone: +0200
1112 mail_from: Monty
1113 reply: monty@no.spam.com
1114 mail_to: "Thimble Smith" <tim@no.spam.com>
1115 sbj: UTF-8
1116 txt: >>>>> "Thimble" == Thimble Smith writes:
1117 Thimble> Hi. I think this is a good idea. Is anyone familiar
1118 Thimble> with UTF-8 or Unicode? Otherwise, I´ll put this on my
1119 Thimble> TODO list and see what happens.
1120 Yes, please do that.
1121 Regards,
1122 Monty
1123 file: inbox-jani-1
1124 hash: 190402944
1125 1 row in set (0.09 sec)
1126
1127 Using the --safe-updates Option
1128 For beginners, a useful startup option is --safe-updates (or
1129 --i-am-a-dummy, which has the same effect). It is helpful for cases
1130 when you might have issued a DELETE FROM tbl_name statement but
1131 forgotten the WHERE clause. Normally, such a statement deletes all rows
1132 from the table. With --safe-updates, you can delete rows only by
1133 specifying the key values that identify them. This helps prevent
1134 accidents.
1135
1136 When you use the --safe-updates option, mysql issues the following
1137 statement when it connects to the MariaDB server:
1138
1139 SET sql_safe_updates=1, sql_select_limit=1000, sql_max_join_size=1000000;
1140
1141 The SET statement has the following effects:
1142
1143 • You are not allowed to execute an UPDATE or DELETE statement unless
1144 you specify a key constraint in the WHERE clause or provide a LIMIT
1145 clause (or both). For example:
1146
1147 UPDATE tbl_name SET not_key_column=val WHERE key_column=val;
1148 UPDATE tbl_name SET not_key_column=val LIMIT 1;
1149
1150 • The server limits all large SELECT results to 1,000 rows unless the
1151 statement includes a LIMIT clause.
1152
1153 • The server aborts multiple-table SELECT statements that probably
1154 need to examine more than 1,000,000 row combinations.
1155
1156 To specify limits different from 1,000 and 1,000,000, you can override
1157 the defaults by using the --select-limit and --max-join-size options:
1158
1159 shell> mysql --safe-updates --select-limit=500 --max-join-size=10000
1160
1161 Disabling mysql Auto-Reconnect
1162 If the mysql client loses its connection to the server while sending a
1163 statement, it immediately and automatically tries to reconnect once to
1164 the server and send the statement again. However, even if mysql
1165 succeeds in reconnecting, your first connection has ended and all your
1166 previous session objects and settings are lost: temporary tables, the
1167 autocommit mode, and user-defined and session variables. Also, any
1168 current transaction rolls back. This behavior may be dangerous for you,
1169 as in the following example where the server was shut down and
1170 restarted between the first and second statements without you knowing
1171 it:
1172
1173 mysql> SET @a=1;
1174 Query OK, 0 rows affected (0.05 sec)
1175 mysql> INSERT INTO t VALUES(@a);
1176 ERROR 2006: MySQL server has gone away
1177 No connection. Trying to reconnect...
1178 Connection id: 1
1179 Current database: test
1180 Query OK, 1 row affected (1.30 sec)
1181 mysql> SELECT * FROM t;
1182 +------+
1183 | a |
1184 +------+
1185 | NULL |
1186 +------+
1187 1 row in set (0.05 sec)
1188
1189 The @a user variable has been lost with the connection, and after the
1190 reconnection it is undefined. If it is important to have mysql
1191 terminate with an error if the connection has been lost, you can start
1192 the mysql client with the --skip-reconnect option.
1193
1195 Copyright 2007-2008 MySQL AB, 2008-2010 Sun Microsystems, Inc.,
1196 2010-2019 MariaDB Foundation
1197
1198 This documentation is free software; you can redistribute it and/or
1199 modify it only under the terms of the GNU General Public License as
1200 published by the Free Software Foundation; version 2 of the License.
1201
1202 This documentation is distributed in the hope that it will be useful,
1203 but WITHOUT ANY WARRANTY; without even the implied warranty of
1204 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1205 General Public License for more details.
1206
1207 You should have received a copy of the GNU General Public License along
1208 with the program; if not, write to the Free Software Foundation, Inc.,
1209 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA or see
1210 http://www.gnu.org/licenses/.
1211
1212
1214 1. Bug#25946
1215 http://bugs.mysql.com/bug.php?id=25946
1216
1218 For more information, please refer to the MariaDB Knowledge Base,
1219 available online at https://mariadb.com/kb/
1220
1222 MariaDB Foundation (http://www.mariadb.org/).
1223
1224
1225
1226MariaDB 10.5 27 June 2019 MARIADB(1)