MDB\_DUMP(1) General Commands Manual MDB\_DUMP(1)

# [NAME](#NAME)

mdb\_dump - LMDB environment export tool

# [SYNOPSIS](#SYNOPSIS)

**mdb\_dump** \[**-V**] \[**-f file]** \[**-l**] \[**-n**] \[**-p**] \[**-a** | **-s subdb]**  **envpath**

# [DESCRIPTION](#DESCRIPTION)

The **mdb\_dump** utility reads a database and writes its contents to the standard output using a portable flat-text format understood by the [**mdb\_load**(1)](/man/os/lmdb/mdb_load.1) utility.

# [OPTIONS](#OPTIONS)

[**-V**](#V)

Write the library version number to the standard output, and exit.

[**-f** file](#f)

Write to the specified file instead of to the standard output.

[**-l**](#l)

List the databases stored in the environment. Just the names will be listed, no data will be output.

[**-n**](#n)

Dump an LMDB database which does not use subdirectories.

[**-p**](#p)

If characters in either the key or data items are printing characters (as defined by [isprint(3)](/man/os/lmdb/isprint.3)), output them directly. This option permits users to use standard text editors and tools to modify the contents of databases.

Note: different systems may have different notions about what characters are considered printing characters, and databases dumped in this manner may be less portable to external systems.

[**-a**](#a)

Dump all of the subdatabases in the environment.

[**-s** subdb](#s)

Dump a specific subdatabase. If no database is specified, only the main database is dumped.

# [DIAGNOSTICS](#DIAGNOSTICS)

Exit status is zero if no errors occur. Errors result in a non-zero exit status and a diagnostic message being written to standard error.

Dumping databases that use user-defined comparison functions will output records with the ordering imposed by those comparison functions. If **mdb\_load** is invoked without including the **-a** option when reloading those records, the new databases will likely be damaged beyond repair, permitting neither record storage nor retrieval.

# [SEE ALSO](#SEE_ALSO)

[**mdb\_load**(1)](/man/os/lmdb/mdb_load.1)

# [AUTHOR](#AUTHOR)

Howard Chu of Symas Corporation <http://www.symas.com>

2015/09/30 LMDB 0.9.17

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Document: mdb_dump(1) from lmdb 0.9.35-r2 (Chainguard OS)
Source: https://github.com/LMDB/lmdb.git