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] [-d ahr] [-f output] [-h home] [-P password] [-s
10 database] 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 -d Dump the specified database in a format helpful for debugging
26 the Berkeley DB library routines.
27 a Display all information.
29 h Display only page headers.
31 r Do not display the free-list or pages on the free list.
33 This mode is used by the recovery tests.
34 The output format of the -d option is not standard and may
36 change, without notice, between releases of the Berkeley DB
37 library.
38 -f output
40 Write to the specified output file instead of to the standard
41 output.
42 -h home
44 Specify a home directory for the database environment; by
45 default, the current working directory is used.
46 -k Dump record numbers from Queue and Recno databases as keys.
48 -l List the databases stored in the file.
50 -N Do not acquire shared region mutexes while running. Other prob‐
52 lems, such as potentially fatal errors in Berkeley DB, will be
53 ignored as well. This option is intended only for debugging
54 errors, and should not be used under any other circumstances.
55 -P password
57 Specify an environment password. Although Berkeley DB utilities
58 overwrite password strings as soon as possible, be aware there
59 may be a window of vulnerability on systems where unprivileged
60 users can see command-line arguments or where utilities are not
61 able to overwrite the memory containing the command-line argu‐
62 ments.
63 -p If characters in either the key or data items are printing char‐
65 acters (as defined by isprint(3)), use printing characters in
66 file to represent them. This option permits users to use stan‐
67 dard text editors and tools to modify the contents of databases.
68 Note: different systems may have different notions about what
70 characters are considered printing characters, and databases
71 dumped in this manner may be less portable to external systems.
72 -R Aggressively salvage data from a possibly corrupt file. The -R
74 flag differs from the -r option in that it will return all pos‐
75 sible data from the file at the risk of also returning already
76 deleted or otherwise nonsensical items. Data dumped in this
77 fashion will almost certainly have to be edited by hand or other
78 means before the data is ready for reload into another database
79 -r Salvage data from a possibly corrupt file. When used on a
81 uncorrupted database, this option should return equivalent data
82 to a normal dump, but most likely in a different order.
83 -s database
85 Specify a single database to dump. If no database is specified,
86 all databases in the database file are dumped.
87 -V Write the library version number to the standard output, and
89 exit.
90 Dumping and reloading Hash databases that use user-defined hash func‐
92 tions will result in new databases that use the default hash function.
93 Although using the default hash function may not be optimal for the new
94 database, it will continue to work correctly.
95 Dumping and reloading Btree databases that use user-defined prefix or
97 comparison functions will result in new databases that use the default
98 prefix and comparison functions. In this case, it is quite likely that
99 the database will be damaged beyond repair permitting neither record
100 storage or retrieval.
101 The only available workaround for either case is to modify the sources
103 for the db_load utility to load the database using the correct hash,
104 prefix, and comparison functions.
105 The db_dump utility output format is documented in the Dump Output For‐
107 mats section of the Berkeley DB Reference Guide.
108 The db_dump utility may be used with a Berkeley DB environment (as
110 described for the -h option, the environment variable DB_HOME, or
111 because the utility was run in a directory containing a Berkeley DB
112 environment). In order to avoid environment corruption when using a
113 Berkeley DB environment, db_dump should always be given the chance to
114 detach from the environment and exit gracefully. To cause db_dump to
115 release all environment resources and exit cleanly, send it an inter‐
116 rupt signal (SIGINT).
117 Even when using a Berkeley DB database environment, the db_dump utility
119 does not use any kind of database locking if it is invoked with the -d,
120 -R, or -r arguments. If used with one of these arguments, the db_dump
121 utility may only be safely run on databases that are not being modified
122 by any other process; otherwise, the output may be corrupt.
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125 The db_dump utility exits 0 on success, and >0 if an error occurs.
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128 DB_HOME
129 If the -h option is not specified and the environment variable
130 DB_HOME is set, it is used as the path of the database home, as
131 described in DB_ENV->open.
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134 db_archive(1) db_checkpoint(1) db_deadlock(1) db_hotbackup(1)
135 db_log_verify(1) db_load(1) db_printlog(1) db_recover(1) db_repli‐
136 cate(1) db_stat(1) db_tuner(1) db_upgrade(1) db_verify(1)
137BerkeleyDB 5.3.21 06 December 2016 DB_DUMP(1)