1DB_LOAD(1) BerkeleyDB Utilities DB_LOAD(1)
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6 db_load - Read and load data from standard input
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9 db_load [-nTV] [-c name=value] [-f input] [-h home] [-P password] [-t
10 btree | hash | queue | recno] file
11 db_load [-r lsn | fileid] [-h home] [-P password] file
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15 The db_load utility reads from the standard input and loads it into the
16 database file. The database file is created if it does not already
17 exist.
18 The input to db_load must be in the output format specified by the
20 db_dump utility, or as specified by the -T option below.
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23 -c name=value
24 Specify configuration options ignoring any value they may have
25 based on the input. The command-line format is name=value. See
26 the Supported Keywords section below for a list of keywords sup‐
27 ported by the -c option.
28 -f input
30 Read from the specified input file instead of from the standard
31 input.
32 -h home
34 Specify a home directory for the database environment.
35 If a home directory is specified, the database environment is
37 opened using the DB_INIT_LOCK, DB_INIT_LOG, DB_INIT_MPOOL,
38 DB_INIT_TXN, and DB_USE_ENVIRON flags to DB_ENV->open. (This
39 means that db_load can be used to load data into databases while
40 they are in use by other processes.) If the DB_ENV->open call
41 fails, or if no home directory is specified, the database is
42 still updated, but the environment is ignored; for example, no
43 locking is done.
44 -n Do not overwrite existing keys in the database when loading into
46 an already existing database. If a key/data pair cannot be
47 loaded into the database for this reason, a warning message is
48 displayed on the standard error output, and the key/data pair
49 are skipped.
50 -P password
52 Specify an environment password. Although Berkeley DB utilities
53 overwrite password strings as soon as possible, be aware there
54 may be a window of vulnerability on systems where unprivileged
55 users can see command-line arguments or where utilities are not
56 able to overwrite the memory containing the command-line argu‐
57 ments.
58 -r Reset the database's file ID or log sequence numbers (LSNs).
60 All database pages in transactional environments contain refer‐
62 ences to the environment's log records. In order to copy a
63 database into a different database environment, database page
64 references to the old environment's log records must be reset,
65 otherwise data corruption can occur when the database is modi‐
66 fied in the new environment. The -r lsn option resets a data‐
67 base's log sequence numbers.
68 All databases contain an ID string used to identify the database
70 in the database environment cache. If a database is copied, and
71 used in the same environment as another file with the same ID
72 string, corruption can occur. The -r fileid option resets a
73 database's file ID to a new value.
74 In both cases, the physical file specified by the file argument
76 is modified in-place.
77 -T The -T option allows non-Berkeley DB applications to easily load
79 text files into databases.
80 If the database to be created is of type Btree or Hash, or the
82 keyword keys is specified as set, the input must be paired lines
83 of text, where the first line of the pair is the key item, and
84 the second line of the pair is its corresponding data item. If
85 the database to be created is of type Queue or Recno and the
86 keyword keys is not set, the input must be lines of text, where
87 each line is a new data item for the database.
88 A simple escape mechanism, where newline and backslash (\) char‐
90 acters are special, is applied to the text input. Newline char‐
91 acters are interpreted as record separators. Backslash charac‐
92 ters in the text will be interpreted in one of two ways: If the
93 backslash character precedes another backslash character, the
94 pair will be interpreted as a literal backslash. If the back‐
95 slash character precedes any other character, the two characters
96 following the backslash will be interpreted as a hexadecimal
97 specification of a single character; for example, \0a is a new‐
98 line character in the ASCII character set.
99 For this reason, any backslash or newline characters that natu‐
101 rally occur in the text input must be escaped to avoid misinter‐
102 pretation by db_load.
103 If the -T option is specified, the underlying access method type
105 must be specified using the -t option.
106 -t Specify the underlying access method. If no -t option is speci‐
108 fied, the database will be loaded into a database of the same
109 type as was dumped; for example, a Hash database will be created
110 if a Hash database was dumped.
111 Btree and Hash databases may be converted from one to the other.
113 Queue and Recno databases may be converted from one to the
114 other. If the -k option was specified on the call to db_dump
115 then Queue and Recno databases may be converted to Btree or
116 Hash, with the key being the integer record number.
117 -V Write the library version number to the standard output, and
119 exit.
120 The db_load utility may be used with a Berkeley DB environment (as
122 described for the -h option, the environment variable DB_HOME, or
123 because the utility was run in a directory containing a Berkeley DB
124 environment). In order to avoid environment corruption when using a
125 Berkeley DB environment, db_load should always be given the chance to
126 detach from the environment and exit gracefully. To cause db_load to
127 release all environment resources and exit cleanly, send it an inter‐
128 rupt signal (SIGINT).
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131 The db_load utility exits 0 on success, 1 if one or more key/data pairs
132 were not loaded into the database because the key already existed, and
133 >1 if an error occurs.
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136 DB_HOME
137 If the -h option is not specified and the environment variable
138 DB_HOME is set, it is used as the path of the database home, as
139 described in DB_ENV->open.
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142 The db_load utility can be used to load text files into databases. For
143 example, the following command loads the standard UNIX /etc/passwd file
144 into a database, with the login name as the key item and the entire
145 password entry as the data item:
146 awk -F: '{print $1; print $0}' < /etc/passwd |
148 sed 's/\\/\\\\/g' | db_load -T -t hash passwd.db
149 Note that backslash characters naturally occurring in the text are
151 escaped to avoid interpretation as escape characters by db_load.
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154 The following keywords are supported for the -c command-line ption to
155 the db_load utility. See DB->open for further discussion of these key‐
156 words and what values should be specified.
157 The parenthetical listing specifies how the value part of the
159 name=value pair is interpreted. Items listed as (boolean) expect value
160 to be 1 (set) or 0 (unset). Items listed as (number) convert value to
161 a number. Items listed as (string) use the string value without modi‐
162 fication.
163 bt_minkey (number)
165 The minimum number of keys per page.
166 chksum (boolean)
168 Enable page checksums.
169 database (string)
171 The database to load.
172 db_lorder (number)
174 The byte order for integers in the stored database metadata.
175 db_pagesize (number)
177 The size of database pages, in bytes.
178 duplicates (boolean)
180 The value of the DB_DUP flag.
181 dupsort (boolean)
183 The value of the DB_DUPSORT flag.
184 extentsize (number)
186 The size of database extents, in pages, for Queue databases con‐
187 figured to use extents.
188 h_ffactor (number)
190 The density within the Hash database.
191 h_nelem (number)
193 The size of the Hash database.
194 keys (boolean)
196 Specify whether keys are present for Queue or Recno databases.
197 re_len (number)
199 Specify fixed-length records of the specified length.
200 re_pad (string)
202 Specify the fixed-length record pad character.
203 recnum (boolean)
205 The value of the DB_RECNUM flag.
206 renumber (boolean)
208 The value of the DB_RENUMBER flag.
209 subdatabase (string)
211 The subdatabase to load.
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214 db_archive(1) db_checkpoint(1) db_deadlock(1) db_dump(1) db_hot‐
215 backup(1) db_log_verify(1) db_printlog(1) db_recover(1) db_replicate(1)
216 db_stat(1) db_tuner(1) db_upgrade(1) db_verify(1)
217BerkeleyDB 5.3.21 06 December 2016 DB_LOAD(1)