1DB_DUMP(1) BerkeleyDB Utilities DB_DUMP(1)
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6 db_dump - Write database file using flat-text format
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9 db_dump [-klNpRrV] [-b blob-dir] [-d ahr] [-f output] [-h home] [-P
10 password] [-s database] [-D bytes] file
11 db_dump [-kNpV] [-d ahr] [-f output] [-h home] -m database
13 db_dump185 [-p] [-f output] file
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17 The db_dump utility reads the database file and writes it to the stan‐
18 dard output using a portable flat-text format understood by the db_load
19 utility. The file argument must be a file produced using the Berkeley
20 DB library functions. The db_dump185 utility is similar to the db_dump
21 utility, except that it reads databases in the format used by Berkeley
22 DB versions 1.85 and 1.86.
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25 -b blob-dir
26 Specifies the directory where BLOB data is stored for the data‐
27 base you are dumping.
28 -d Dump the specified database in a format helpful for debugging
30 the Berkeley DB library routines.
31 a Display all information.
33 h Display only page headers.
35 r Do not display the free-list or pages on the free list.
37 This mode is used by the recovery tests.
38 The output format of the -d option is not standard and may
40 change, without notice, between releases of the Berkeley DB
41 library.
42 -D bytes
44 Specifies the maximum number of bytes to dump for each key/data
45 item found in the specified database. This option is only valid
46 when -da is also specified. This option overrides the value set
47 for the "set_data_len" parameter in your DB_CONFIG file, if any.
48 -f output
50 Write to the specified output file instead of to the standard
51 output.
52 -h home
54 Specify a home directory for the database environment; by
55 default, the current working directory is used.
56 -k Dump record numbers from Queue and Recno databases as keys.
58 -l List the databases stored in the file.
60 -N Do not acquire shared region mutexes while running. Other prob‐
62 lems, such as potentially fatal errors in Berkeley DB, will be
63 ignored as well. This option is intended only for debugging
64 errors, and should not be used under any other circumstances.
65 -P password
67 Specify an environment password. Although Berkeley DB utilities
68 overwrite password strings as soon as possible, be aware there
69 may be a window of vulnerability on systems where unprivileged
70 users can see command-line arguments or where utilities are not
71 able to overwrite the memory containing the command-line argu‐
72 ments.
73 -p If characters in either the key or data items are printing char‐
75 acters (as defined by isprint(3)), use printing characters in
76 file to represent them. This option permits users to use stan‐
77 dard text editors and tools to modify the contents of databases.
78 Note: different systems may have different notions about what
80 characters are considered printing characters, and databases
81 dumped in this manner may be less portable to external systems.
82 -R Aggressively salvage data from a possibly corrupt file. The -R
84 flag differs from the -r option in that it will return all pos‐
85 sible data from the file at the risk of also returning already
86 deleted or otherwise nonsensical items. Data dumped in this
87 fashion will almost certainly have to be edited by hand or other
88 means before the data is ready for reload into another database
89 -r Salvage data from a possibly corrupt file. When used on a
91 uncorrupted database, this option should return equivalent data
92 to a normal dump, but most likely in a different order.
93 -s database
95 Specify a single database to dump. If no database is specified,
96 all databases in the database file are dumped.
97 -V Write the library version number to the standard output, and
99 exit.
100 Dumping and reloading Hash databases that use user-defined hash func‐
102 tions will result in new databases that use the default hash function.
103 Although using the default hash function may not be optimal for the new
104 database, it will continue to work correctly.
105 Dumping and reloading Btree databases that use user-defined prefix or
107 comparison functions will result in new databases that use the default
108 prefix and comparison functions. In this case, it is quite likely that
109 the database will be damaged beyond repair permitting neither record
110 storage or retrieval.
111 The only available workaround for either case is to modify the sources
113 for the db_load utility to load the database using the correct hash,
114 prefix, and comparison functions.
115 The db_dump utility output format is documented in the Dump Output For‐
117 mats section of the Berkeley DB Reference Guide.
118 The db_dump utility may be used with a Berkeley DB environment (as
120 described for the -h option, the environment variable DB_HOME, or
121 because the utility was run in a directory containing a Berkeley DB
122 environment). In order to avoid environment corruption when using a
123 Berkeley DB environment, db_dump should always be given the chance to
124 detach from the environment and exit gracefully. To cause db_dump to
125 release all environment resources and exit cleanly, send it an inter‐
126 rupt signal (SIGINT).
127 Even when using a Berkeley DB database environment, the db_dump utility
129 does not use any kind of database locking if it is invoked with the -d,
130 -R, or -r arguments. If used with one of these arguments, the db_dump
131 utility may only be safely run on databases that are not being modified
132 by any other process; otherwise, the output may be corrupt.
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135 The db_dump utility exits 0 on success, and >0 if an error occurs.
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138 DB_HOME
139 If the -h option is not specified and the environment variable
140 DB_HOME is set, it is used as the path of the database home, as
141 described in DB_ENV->open.
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144 db_archive(1) db_checkpoint(1) db_deadlock(1) db_hotbackup(1)
145 db_log_verify(1) db_load(1) db_printlog(1) db_recover(1) db_repli‐
146 cate(1) db_stat(1) db_tuner(1) db_upgrade(1) db_verify(1)
147BerkeleyDB 5.3.28 06 December 2016 DB_DUMP(1)