PG_DUMP(1)
π pg_dump(1) β PostgreSQL 14.24 Documentation π
β¨ NAME β¨
pg_dump β extract a PostgreSQL database into a script file or other archive file
π«Ά SYNOPSIS π«Ά
pg_dump [connection-option...] [option...] [dbname]
π DESCRIPTION π
Okay bestie, so pg_dump is the utility for backing up a PostgreSQL database, and it literally makes consistent backups even if the database is being used concurrently. The way it does not block other users accessing the database β readers or writers β is honestly iconic. π
One big thing: pg_dump only dumps a single database. If you need to back up an entire cluster, or back up global objects that are common to all databases in a cluster (such as roles and tablespaces), use pg_dumpall(1). Periodt.
Dumps can be output in script or archive file formats. Script dumps are plain-text files containing the SQL commands required to reconstruct the database to the state it was in at the time it was saved. To restore from such a script, feed it to psql(1). Script files can be used to reconstruct the database even on other machines and other architectures; with some modifications, even on other SQL database products. π¦
The alternative archive file formats must be used with pg_restore(1) to rebuild the database. They allow pg_restore to be selective about what is restored, or even to reorder the items prior to being restored. The archive file formats are designed to be portable across architectures. β¨
When used with one of the archive file formats and combined with pg_restore, pg_dump provides a flexible archival and transfer mechanism. pg_dump can be used to backup an entire database, then pg_restore can be used to examine the archive and/or select which parts of the database are to be restored. The most flexible output file formats are the βcustomβ format (-Fc) and the βdirectoryβ format (-Fd). They allow for selection and reordering of all archived items, support parallel restoration, and are compressed by default. The βdirectoryβ format is the only format that supports parallel dumps. π
While running pg_dump, one should examine the output for any warnings (printed on standard error), especially in light of the limitations listed below. π
β οΈ Warning β οΈ Restoring a dump causes the destination to execute arbitrary code of the source superusers' choice. Partial dumps and partial restores do not limit that. If the source superusers are not trusted, the dumped SQL statements must be inspected before restoring. Non-plain-text dumps can be inspected by usingpg_restore's--fileoption. Note that the client running the dump and restore need not trust the source or destination superusers. π
πΈ OPTIONS πΈ
The following command-line options control the content and format of the output.
dbnameβ Specifies the name of the database to be dumped. If this is not specified, the environment variablePGDATABASEis used. If that is not set, the user name specified for the connection is used. π«Ά-a,--data-onlyβ Dump only the data, not the schema (data definitions). Table data, large objects, and sequence values are dumped. This option is similar to, but for historical reasons not identical to, specifying--section=data. β¨-b,--blobsβ Include large objects in the dump. This is the default behavior except when--schema,--table, or--schema-onlyis specified. The-bswitch is therefore only useful to add large objects to dumps where a specific schema or table has been requested. Note that blobs are considered data and therefore will be included when--data-onlyis used, but not when--schema-onlyis. π-B,--no-blobsβ Exclude large objects in the dump. When both-band-Bare given, the behavior is to output large objects, when data is being dumped, see the-bdocumentation. π-c,--cleanβ Output commands toDROPall the dumped database objects prior to outputting the commands for creating them. This option is useful when the restore is to overwrite an existing database. If any of the objects do not exist in the destination database, ignorable error messages will be reported during restore, unless--if-existsis also specified. This option is ignored when emitting an archive (non-text) output file. For the archive formats, you can specify the option when you callpg_restore. π§¨-C,--createβ Begin the output with a command to create the database itself and reconnect to the created database. (With a script of this form, it doesn't matter which database in the destination installation you connect to before running the script.) If--cleanis also specified, the script drops and recreates the target database before reconnecting to it. With--create, the output also includes the database's comment if any, and any configuration variable settings that are specific to this database, that is, anyALTER DATABASE ... SET ...andALTER ROLE ... IN DATABASE ... SET ...commands that mention this database. Access privileges for the database itself are also dumped, unless--no-aclis specified. This option is ignored when emitting an archive (non-text) output file. For the archive formats, you can specify the option when you callpg_restore. π-epattern,--extension=patternβ Dump only extensions matching pattern. When this option is not specified, all non-system extensions in the target database will be dumped. Multiple extensions can be selected by writing multiple-eswitches. The pattern parameter is interpreted as a pattern according to the same rules used bypsql's\dcommands (see Patterns), so multiple extensions can also be selected by writing wildcard characters in the pattern. When using wildcards, be careful to quote the pattern if needed to prevent the shell from expanding the wildcards. Any configuration relation registered bypg_extension_config_dumpis included in the dump if its extension is specified by--extension. π¦
Note When-eis specified,pg_dumpmakes no attempt to dump any other database objects that the selected extension(s) might depend upon. Therefore, there is no guarantee that the results of a specific-extension dump can be successfully restored by themselves into a clean database. π
-Eencoding,--encoding=encodingβ Create the dump in the specified character set encoding. By default, the dump is created in the database encoding. (Another way to get the same result is to set thePGCLIENTENCODINGenvironment variable to the desired dump encoding.) The supported encodings are described in Section 24.3.1. π-ffile,--file=fileβ Send output to the specified file. This parameter can be omitted for file based output formats, in which case the standard output is used. It must be given for the directory output format however, where it specifies the target directory instead of a file. In this case the directory is created bypg_dumpand must not exist before. π-Fformat,--format=formatβ Selects the format of the output. format can be one of the following:p,plainβ Output a plain-text SQL script file (the default). βc,customβ Output a custom-format archive suitable for input intopg_restore. Together with the directory output format, this is the most flexible output format in that it allows manual selection and reordering of archived items during restore. This format is also compressed by default. π₯d,directoryβ Output a directory-format archive suitable for input intopg_restore. This will create a directory with one file for each table and blob being dumped, plus a so-called Table of Contents file describing the dumped objects in a machine-readable format thatpg_restorecan read. A directory format archive can be manipulated with standard Unix tools; for example, files in an uncompressed archive can be compressed with thegziptool. This format is compressed by default and also supports parallel dumps. πt,tarβ Output a tar-format archive suitable for input intopg_restore. The tar format is compatible with the directory format: extracting a tar-format archive produces a valid directory-format archive. However, the tar format does not support compression. Also, when using tar format the relative order of table data items cannot be changed during restore. π
-jnjobs,--jobs=njobsβ Run the dump in parallel by dumping njobs tables simultaneously. This option may reduce the time needed to perform the dump but it also increases the load on the database server. You can only use this option with the directory output format because this is the only output format where multiple processes can write their data at the same time.pg_dumpwill open njobs + 1 connections to the database, so make sure yourmax_connectionssetting is high enough to accommodate all connections. π«Ά
Requesting exclusive locks on database objects while running a parallel dump could cause the dump to fail. The reason is that the pg_dump leader process requests shared locks (ACCESS SHARE) on the objects that the worker processes are going to dump later in order to make sure that nobody deletes them and makes them go away while the dump is running. If another client then requests an exclusive lock on a table, that lock will not be granted but will be queued waiting for the shared lock of the leader process to be released. Consequently any other access to the table will not be granted either and will queue after the exclusive lock request. This includes the worker process trying to dump the table. Without any precautions this would be a classic deadlock situation. To detect this conflict, the pg_dump worker process requests another shared lock using the NOWAIT option. If the worker process is not granted this shared lock, somebody else must have requested an exclusive lock in the meantime and there is no way to continue with the dump, so pg_dump has no choice but to abort the dump. π
For a consistent backup, the database server has to support synchronized snapshots β a feature that landed in PostgreSQL 9.2 for primary servers and in 10 for standbys. With it, database clients can make sure they're all seeing the same data set even though they're on different connections. pg_dump -j uses multiple database connections β it connects once with the leader process and then once again for each worker job. Without synchronized snapshots, those different worker jobs wouldn't be guaranteed to see the same data on each connection, which could hand you an inconsistent backup. π¬
So if you wanna run a parallel dump of a pre-9.2 server, you gotta make sure the database content doesn't change from the moment the leader connects until the last worker job has connected. Easiest way? Halt any data-modifying processes (DDL and DML) touching the database before you start the backup. You also need to pass --no-synchronized-snapshots when running pg_dump -j against a pre-9.2 PostgreSQL server. No cap.
-npattern,--schema=pattern β dump only schemas matching pattern. This selects both the schema itself and all the objects inside it. If you don't specify this option, every non-system schema in the target database gets dumped. Wanna pick multiple schemas? Just write multiple-nswitches. The pattern parameter is interpreted using the same rules as psql's\dcommands (see Patterns below), so you can also grab multiple schemas by throwing wildcard characters into the pattern. When you use wildcards, be careful to quote the pattern if needed so the shell doesn't expand them for you β see Examples below. β¨
Note: when-nis specified,pg_dumpmakes no attempt to dump any other database objects that the selected schema(s) might depend on. So there's no guarantee that a specific-schema dump can be successfully restored by itself into a clean database. π
Note: non-schema objects like blobs don't get dumped when-nis specified. You can add blobs back to the dump with the--blobsswitch.
-Npattern,--exclude-schema=pattern β don't dump any schemas matching pattern. The pattern is interpreted by the same rules as for-n. You can give-Nmore than once to exclude schemas matching any of several patterns.
When both -n and -N are given, the vibe is: dump just the schemas that match at least one -n switch but no -N switches. If -N shows up without -n, then schemas matching -N are excluded from what would otherwise be a normal dump. π«Ά
-O,--no-ownerβ don't output commands that set object ownership to match the original database. By default,pg_dumpissuesALTER OWNERorSET SESSION AUTHORIZATIONstatements to set ownership of the created database objects. Those statements will fail when the script is run unless it's started by a superuser (or the same user that owns all the objects in the script). Wanna make a script that any user can restore, but that gives that user ownership of all the objects? Specify-O. π
This option is ignored when emitting an archive (non-text) output file. For the archive formats, you can specify the option when you call pg_restore.
-R,--no-reconnectβ this option is obsolete but still accepted for backwards compatibility. It's giving retired icon, honestly. π-s,--schema-onlyβ dump only the object definitions (schema), not the data.
This option is the inverse of --data-only. It's similar to β but for historical reasons not identical to β specifying --section=pre-data --section=post-data.
(Do not confuse this with the --schema option, which uses the word βschemaβ in a different meaning. π)
Wanna exclude table data for only a subset of tables in the database? See --exclude-table-data.
-Susername,--superuser=username β specify the superuser user name to use when disabling triggers. This is only relevant if--disable-triggersis used. (Usually it's better to leave this out and instead start the resulting script as superuser.)-tpattern,--table=pattern β dump only tables with names matching pattern. Wanna pick multiple tables? Write multiple-tswitches. The pattern parameter is interpreted using the same rules as psql's\dcommands (see Patterns below), so you can also grab multiple tables by writing wildcard characters in the pattern. When using wildcards, quote the pattern if needed so the shell doesn't expand them β see Examples below. πΈ
As well as tables, this option can dump the definition of matching views, materialized views, foreign tables, and sequences. It will not dump the contents of views or materialized views, and the contents of foreign tables will only be dumped if the corresponding foreign server is specified with --include-foreign-data.
The -n and -N switches have no effect when -t is used, because tables selected by -t get dumped regardless of those switches, and non-table objects won't be dumped.
Note: when-tis specified,pg_dumpmakes no attempt to dump any other database objects the selected table(s) might depend on. So there's no guarantee that a specific-table dump can be successfully restored by itself into a clean database. π
-Tpattern,--exclude-table=pattern β don't dump any tables matching pattern. The pattern is interpreted by the same rules as for-t. You can give-Tmore than once to exclude tables matching any of several patterns.
When both -t and -T are given, the behavior is: dump just the tables that match at least one -t switch but no -T switches. If -T appears without -t, then tables matching -T are excluded from what's otherwise a normal dump. β¨
-v,--verboseβ turns on verbose mode. This makespg_dumpoutput detailed object comments and start/stop times to the dump file, plus progress messages to standard error. Repeat the option and you get additional debug-level messages on standard error. π-V,--versionβ print thepg_dumpversion and exit.-x,--no-privileges,--no-aclβ prevent dumping of access privileges (grant/revoke commands). π ββοΈ-Z 0..9,--compress=0..9β specify the compression level to use. Zero means no compression. For the custom and directory archive formats, this specifies compression of individual table-data segments, and the default is to compress at a moderate level. For plain text output, setting a nonzero compression level compresses the entire output file, as though it had been fed throughgzipβ but the default is not to compress. The tar archive format currently doesn't support compression at all. π--binary-upgradeβ this option is for use by in-place upgrade utilities. Its use for other purposes is not recommended or supported. The behavior of the option may change in future releases without notice. π§--column-inserts,--attribute-insertsβ dump data asINSERTcommands with explicit column names (INSERT INTO table (column, ...) VALUES ...). This makes restoration very slow; it's mainly useful for making dumps that can be loaded into non-PostgreSQL databases. Any error during restoring will cause only the rows that are part of the problematicINSERTto be lost, rather than the entire table contents. π’--disable-dollar-quotingβ disables the use of dollar quoting for function bodies, and forces them to be quoted using SQL standard string syntax.--disable-triggersβ only relevant when creating a data-only dump. It tellspg_dumpto include commands that temporarily disable triggers on the target tables while the data is restored. Use this if you have referential integrity checks or other triggers on the tables that you don't want invoked during data restore. π
Right now, the commands emitted for --disable-triggers must be done as superuser. So you should also specify a superuser name with -S, or preferably be careful to start the resulting script as a superuser.
This option is ignored when emitting an archive (non-text) output file. For the archive formats, you can specify the option when you call pg_restore.
--enable-row-securityβ only relevant when dumping the contents of a table that has row security. By default,pg_dumpsetsrow_securityto off, to make sure all the data gets dumped from the table. If the user doesn't have sufficient privileges to bypass row security, an error gets thrown. This parameter tellspg_dumpto setrow_securityto on instead, letting the user dump the parts of the table contents they actually have access to. πͺ
Heads up: if you use this option right now, you probably also want the dump in INSERT format, since the COPY FROM during restore doesn't support row security.
--exclude-table-data=pattern β don't dump data for any tables matching pattern. The pattern is interpreted by the same rules as for-t.--exclude-table-datacan be given more than once to exclude tables matching any of several patterns. This option is a lifesaver when you need the definition of a particular table even though you don't need the data in it. β¨
Wanna exclude data for all tables in the database? See --schema-only.
--extra-float-digits=ndigits β use the specified value ofextra_float_digitswhen dumping floating-point data, instead of the maximum available precision. Routine dumps made for backup purposes should not use this option. β οΈ--if-existsβ useDROP ... IF EXISTScommands to drop objects in--cleanmode. This suppresses βdoes not existβ errors that might otherwise get reported. This option is not valid unless--cleanis also specified. π--include-foreign-data=foreignserverβ dumps the data of any foreign table whose foreign server matches the foreignserver pattern β¨ and honestly? this one's lowkey powerful. You can grab multiple foreign servers by stacking multiple--include-foreign-dataswitches, OR by putting wildcard characters in the pattern β because foreignserver gets interpreted with the exact same rules psql's\dcommands use (peep Patterns below, iykyk). When you go the wildcard route, please quote that pattern if the shell would otherwise eat it β see Examples below. The one and only thing you can't do: an empty pattern is disallowed, periodt.
π Note: wildcards in --include-foreign-data may result in access to unexpected foreign servers. Not a vibe. Also, to use this option securely, make sure the named server must have a trusted owner.
π Note: when--include-foreign-datais specified,pg_dumpdoes not check that the foreign table is writable. So there is no guarantee that the results of a foreign table dump can be successfully restored β fr fr, no cap.
--insertsβ dumps the data asINSERTcommands instead ofCOPY. Bestie, this makes restoration very slow, okay? It's mainly useful for making dumps that can be loaded into non-PostgreSQL databases. The upside: any error during restoring will cause only the rows that are part of the problematicINSERTto be lost, rather than the entire table contents πΈ. Heads up though β the restore might fail altogether if you've rearranged column order π. The--column-insertsoption is safe against column order changes, though even slower.--load-via-partition-rootβ when dumping data for a table partition, this makes theCOPYorINSERTstatements target the root of the partitioning hierarchy that contains it, rather than the partition itself. So the appropriate partition gets re-determined for each row when the data is loaded π. Useful when you're restoring on a server where rows don't always fall into the same partitions as they did on the original server. When would that happen? For example, if the partitioning column is of typetextand the two systems have different definitions of the collation used to sort the partitioning column. Slay, but also chaos.--lock-wait-timeout=timeoutβ do not wait forever to acquire shared table locks at the beginning of the dump π ββοΈ. Instead, fail if it's unable to lock a table within the specified timeout. The timeout may be specified in any of the formats accepted bySET statement_timeout. (Allowed formats vary depending on the server version you are dumping from, but an integer number of milliseconds is accepted by all versions.) Very "I have boundaries" of it.--no-commentsβ do not dump comments.--no-publicationsβ do not dump publications.--no-security-labelsβ do not dump security labels.--no-subscriptionsβ do not dump subscriptions.--no-syncβ by default,pg_dumpwaits for all files to be written safely to disk. This option makespg_dumpreturn without waiting β faster, yes, but it means a subsequent operating system crash can leave the dump corrupt π. Generally this one is useful for testing but should not be used when dumping data from a production installation. Like, read that twice, bestie.--no-synchronized-snapshotsβ this option allows runningpg_dump -jagainst a pre-9.2 server, see the documentation of the-jparameter for more details π¦.--no-tablespacesβ do not output commands to select tablespaces. With this option, all objects will be created in whichever tablespace is the default during restore.
This option is ignored when emitting an archive (non-text) output file. For the archive formats, you can specify the option when you call pg_restore.
--no-toast-compressionβ do not output commands to set TOAST compression methods. With this option, all columns will be restored with the default compression setting π§.--no-unlogged-table-dataβ do not dump the contents of unlogged tables. This option has no effect on whether or not the table definitions (schema) are dumped β it only suppresses dumping the table data π. Also, data in unlogged tables is always excluded when dumping from a standby server.--on-conflict-do-nothingβ addsON CONFLICT DO NOTHINGtoINSERTcommands. This option is not valid unless--inserts,--column-insertsor--rows-per-insertis also specified. Package deal, no solo acts π .--quote-all-identifiersβ forces quoting of all identifiers. This is recommended when dumping a database from a server whose PostgreSQL major version is different frompg_dump's, or when the output is intended to be loaded into a server of a different major version π«Ά. By default,pg_dumpquotes only identifiers that are reserved words in its own major version β which sometimes results in compatibility issues when you're dealing with servers of other versions that may have slightly different sets of reserved words. Using--quote-all-identifiersprevents such issues, at the price of a harder-to-read dump script. Iconic tradeoff.--restrict-key=restrict_keyβ use the provided string as the psql\restrictkey in the dump output. This can only be specified for plain-text dumps, i.e., when--formatis set toplainor the--formatoption is omitted. If no restrict key is specified,pg_dumpwill generate a random one as needed π². Keys may contain only alphanumeric characters.
This option is primarily intended for testing purposes and other scenarios that require repeatable output (e.g., comparing dump files). It is not recommended for general use, as a malicious server with advance knowledge of the key may be able to inject arbitrary code that will be executed on the machine that runs psql with the dump output π. Do not be casual about this one.
--rows-per-insert=nrowsβ dumps data asINSERTcommands (rather thanCOPY) and controls the maximum number of rows perINSERTcommand β. The value specified must be a number greater than zero. Any error during restoring will cause only the rows that are part of the problematicINSERTto be lost, rather than the entire table contents. Small blast radius, big serve.--section=sectionnameβ only dump the named section. The section name can bepre-data,data, orpost-data. This option can be specified more than once to select multiple sections πΈ. The default is to dump all sections.
So what's in each? The data section contains actual table data, large-object contents, and sequence values. post-data items include definitions of indexes, triggers, rules, and constraints other than validated check constraints. pre-data items include all other data definition items. Chef's kiss breakdown, honestly.
--serializable-deferrableβ use a serializable transaction for the dump, to ensure that the snapshot used is consistent with later database states; but do it by waiting for a point in the transaction stream at which no anomalies can be present, so that there isn't a risk of the dump failing or causing other transactions to roll back with aserialization_failureπ₯. See Chapter 13 for more information about transaction isolation and concurrency control.
This option is not beneficial for a dump which is intended only for disaster recovery. It could be useful for a dump used to load a copy of the database for reporting or other read-only load sharing while the original database continues to be updated π. Without it, the dump may reflect a state which is not consistent with any serial execution of the transactions eventually committed. For example, if batch processing techniques are used, a batch may show as closed in the dump without all of the items which are in the batch appearing π.
It will make no difference if there are no read-write transactions active when pg_dump is started. If read-write transactions are active, the start of the dump may be delayed for an indeterminate length of time β³. Once running, performance with or without the switch is the same.
--snapshot=snapshotnameβ use the specified synchronized snapshot when making a dump of the database (see Table 9.90 for more details).
This option is useful when you need to synchronize the dump with a logical replication slot (see Chapter 49) or with a concurrent session π¦.
In the case of a parallel dump, the snapshot name defined by this option is used rather than taking a new snapshot. No dupe snapshots here.
--strict-namesβ require that each extension (-e/--extension), schema (-n/--schema) and table (-t/--table) qualifier match at least one extension/schema/table in the database to be dumped π . Note that if none of the extension/schema/table qualifiers find matches,pg_dumpwill generate an error even without--strict-names.
This option has no effect on -N/--exclude-schema, -T/--exclude-table, or --exclude-table-data. An exclude pattern failing to match any objects is not considered an error π
ββοΈ. Excludes simply get to ghost things.
--use-set-session-authorizationβ outputs SQL-standardSET SESSION AUTHORIZATIONcommands instead ofALTER OWNERcommands to determine object ownership π. This makes the dump more standards-compatible, but depending on the history of the objects in the dump, it might not restore properly. Also, a dump usingSET SESSION AUTHORIZATIONwill certainly require superuser privileges to restore correctly, whereasALTER OWNERrequires lesser privileges. Choose wisely, bestie.-?,--helpβ show help aboutpg_dumpcommand line arguments, and exit π.
π the database-connection-parameters era
The following command-line options control the database connection parameters. Connective tissue, but make it fashion.
-d dbname,--dbname=dbnameβ specifies the name of the database to connect to. This is equivalent to specifying dbname as the first non-option argument on the command line β. And plot twist: dbname can be a connection string β if so, connection string parameters will override any conflicting command line options. Sneaky but valid.-h host,--host=hostβ specifies the host name of the machine on which the server is running π₯οΈ. If the value begins with a slash, it is used as the directory for the Unix domain socket. The default is taken from thePGHOSTenvironment variable, if set, else a Unix domain socket connection is attempted.-p port,--port=portβ specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections π. Defaults to thePGPORTenvironment variable, if set, or a compiled-in default.-U username,--username=usernameβ user name to connect as π. That's the whole description, she's brief and she's booked.-w,--no-passwordβ never ever prompt for a password. like, never. if the server needs password auth and there's no password available some other way (say, a.pgpassfile), the connection attempt just fails, no drama. this one is iconic for batch jobs and scripts where literally no human is around to type a password π-W,--passwordβ forcespg_dumpto prompt for a password before it connects to a database.
ngl this one is never actually essential, because pg_dump will automatically prompt if the server demands password authentication. but here's the tea: pg_dump will waste a whole connection attempt just to find out the server wants a password. so sometimes it's worth typing -W to skip that extra connection attempt π
--role=*rolename*β picks a role name to be used when creating the dump. this makespg_dumprun aSET ROLE rolenamecommand right after connecting to the database. so useful when the authenticated user (the one you gave with-U) doesn't have the privilegespg_dumpneeds, but can switch to a role that has the required rights. some installations have a whole policy against logging in directly as a superuser, and this option lets you make dumps without violating that policy β¨
πΈ ENVIRONMENT πΈ
PGDATABASEPGHOSTPGOPTIONSPGPORTPGUSER
these are the default connection parameters, bestie. set them once, vibe forever.
PG_COLORβ says whether to use color in diagnostic messages. the possible values arealways,autoandnever.
this utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 34.15). so yes, the whole libpq env var family is invited to the party π
π©Ί DIAGNOSTICS π©Ί
pg_dump internally executes SELECT statements. so if you're having problems running pg_dump, make sure you can actually select information from the database using, for example, psql(1). also, any default connection settings and environment variables used by the libpq front-end library will apply. iykyk π
the database activity of pg_dump is normally collected by the statistics collector. if that's not the vibe for you, you can set parameter track_counts to false via PGOPTIONS or the ALTER USER command.
π NOTES π
if your database cluster has any local additions to the template1 database, be careful β restore the output of pg_dump into a truly empty database, otherwise you're likely to get errors due to duplicate definitions of the added objects. to make an empty database without any local additions, copy from template0 not template1, for example:
CREATE DATABASE foo WITH TEMPLATE template0;
when a data-only dump is chosen and the option --disable-triggers is used, pg_dump emits commands to disable triggers on user tables before inserting the data, and then commands to re-enable them after the data has been inserted. π¨ warning bestie: if the restore is stopped in the middle, the system catalogs might be left in the wrong state.
the dump file produced by pg_dump does not contain the statistics used by the optimizer to make query planning decisions. therefore, it is wise to run ANALYZE after restoring from a dump file to ensure optimal performance; see Section 25.1.3 and Section 25.1.6 for more information. do it for the plot π«Ά
because pg_dump is used to transfer data to newer versions of PostgreSQL, the output of pg_dump can be expected to load into PostgreSQL server versions newer than pg_dump's version. pg_dump can also dump from PostgreSQL servers older than its own version. (currently, servers back to version 8.0 are supported.) however, pg_dump cannot dump from PostgreSQL servers newer than its own major version β it will refuse to even try, rather than risk making an invalid dump. also, it is not guaranteed that pg_dump's output can be loaded into a server of an older major version β not even if the dump was taken from a server of that version. loading a dump file into an older server may require manual editing of the dump file to remove syntax not understood by the older server. use of the --quote-all-identifiers option is recommended in cross-version cases, as it can prevent problems arising from varying reserved-word lists in different PostgreSQL versions π₯
when dumping logical replication subscriptions, pg_dump will generate CREATE SUBSCRIPTION commands that use the connect = false option, so that restoring the subscription does not make remote connections for creating a replication slot or for initial table copy. that way, the dump can be restored without requiring network access to the remote servers. it is then up to the user to reactivate the subscriptions in a suitable way. if the involved hosts have changed, the connection information might have to be changed. it might also be appropriate to truncate the target tables before initiating a new full table copy. main character energy, honestly π
it is generally recommended to use the -X (--no-psqlrc) option when restoring a database from a plain-text pg_dump script to ensure a clean restore process and prevent potential conflicts with non-default psql configurations. tiny flag, huge slay β
β¨ EXAMPLES β¨
to dump a database called mydb into an SQL-script file:
$ pg_dump mydb > db.sql
to reload such a script into a (freshly created) database named newdb:
$ psql -X -d newdb -f db.sql
to dump a database into a custom-format archive file:
$ pg_dump -Fc mydb > db.dump
to dump a database into a directory-format archive:
$ pg_dump -Fd mydb -f dumpdir
to dump a database into a directory-format archive in parallel with 5 worker jobs:
$ pg_dump -Fd mydb -j 5 -f dumpdir
to reload an archive file into a (freshly created) database named newdb:
$ pg_restore -d newdb db.dump
to reload an archive file into the same database it was dumped from, discarding the current contents of that database:
$ pg_restore -d postgres --clean --create db.dump
to dump a single table named mytab:
$ pg_dump -t mytab mydb > db.sql
to dump all tables whose names start with emp in the detroit schema, except for the table named employee_log:
$ pg_dump -t 'detroit.emp*' -T detroit.employee_log mydb > db.sql
to dump all schemas whose names start with east or west and end in gsm, excluding any schemas whose names contain the word test:
$ pg_dump -n 'east*gsm' -n 'west*gsm' -N '*test*' mydb > db.sql
the same, using regular expression notation to consolidate the switches:
$ pg_dump -n '(east|west)*gsm' -N '*test*' mydb > db.sql
to dump all database objects except for tables whose names begin with ts_:
$ pg_dump -T 'ts_*' mydb > db.sql
to specify an upper-case or mixed-case name in -t and related switches, you need to double-quote the name; else it will be folded to lower case (see Patterns below). but double quotes are special to the shell, so in turn they must be quoted. thus, to dump a single table with a mixed-case name, you need something like
$ pg_dump -t "\"MixedCaseName\"" mydb > mytab.sql
π SEE ALSO π
pg_dumpall(1), pg_restore(1), psql(1)
and that's the whole page, bestie!! you just read your way through the PostgreSQL 14.24 edition of PG_DUMP(1), dated 2026 β go forth and dump responsibly, back up your fave databases, and remember: never restore into template1 unless you wanna find out πβ¨ππ¦π
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