qhb_dumpall

qhb_dumpall — extract a QHB database cluster into a script file

Synopsis

qhb_dumpall [connection-option...] [option...]

qhb_dumpall — is a utility for writing out (“dumping”) all QHB databases of a cluster into one script file. The script file contains SQL commands that can be used as input to [psql] to restore the databases. It does this by calling qhb_dump for each database in the cluster. qhb_dumpall also dumps global objects that are common to all databases, namely database roles, tablespaces, and privilege grants for configuration parameters. (qhb_dump does not save these objects.)

Since qhb_dumpall reads tables from all databases you will most likely have to connect as a database superuser in order to produce a complete dump. Also you will need superuser privileges to execute the saved script in order to be allowed to add roles and create databases.

The SQL script will be written to the standard output. Use the -f/--file option or shell operators to redirect it into a file.

qhb_dumpall needs to connect several times to the QHB server (once per database). If you use password authentication it will ask for a password each time. It is convenient to have a ~/.pgpass file in such cases. See Section The Password File for more information.

Options

The following command-line options control the content and format of the output.

-a
--data-only
Dump only the data, not the schema (data definitions).

-c
--clean
Emit SQL commands to DROP all the dumped databases, roles, and tablespaces before recreating them. This option is useful when the restore is to overwrite an existing cluster. If any of the objects do not exist in the destination cluster, ignorable error messages will be reported during restore, unless --if-exists is also specified.

-E encoding
--encoding=encoding
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 the PGCLIENTENCODING environment variable to the desired dump encoding.)

-f filename
--file=filename
Send output to the specified file. If this is omitted, the standard output is used.

-g
--globals-only
Dump only global objects (roles and tablespaces), no databases.

-O
--no-owner
Do not output commands to set ownership of objects to match the original database. By default, qhb_dumpall issues ALTER OWNER or SET SESSION AUTHORIZATION statements to set ownership of created schema elements. These statements will fail when the script is run unless it is started by a superuser (or the same user that owns all of the objects in the script). To make a script that can be restored by any user, but will give that user ownership of all the objects, specify -O.

-r
--roles-only
Dump only roles, no databases or tablespaces.

-s
--schema-only
Dump only the object definitions (schema), not data.

-S username
--superuser=username
Specify the superuser user name to use when disabling triggers. This is relevant only if --disable-triggers is used. (Usually, it's better to leave this out, and instead start the resulting script as superuser.)

-t
--tablespaces-only
Dump only tablespaces, no databases or roles.

-v
--verbose
Specifies verbose mode. This will cause qhb_dumpall to output start/stop times to the dump file, and progress messages to standard error. Repeating the option causes additional debug-level messages to appear on standard error. The option is also passed down to qhb_dump.

-V
--version
Print the qhb_dumpall version and exit.

-x
--no-privileges
--no-acl
Prevent dumping of access privileges (grant/revoke commands).

--binary-upgrade
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.

--column-inserts
--attribute-inserts
Dump data as INSERT commands with explicit column names (INSERT INTO table (column, ...) VALUES ...). This will make restoration very slow; it is mainly useful for making dumps that can be loaded into non-QHB databases.

--disable-dollar-quoting
This option disables the use of dollar quoting for function bodies, and forces them to be quoted using SQL standard string syntax.

--disable-triggers
This option is relevant only when creating a data-only dump. It instructs qhb_dumpall to include commands to 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 do not want to invoke during data restore.

Presently, 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.

--exclude-database=pattern
Do not dump databases whose name matches pattern. Multiple patterns can be excluded by writing multiple --exclude-database switches. The pattern parameter is interpreted as a pattern according to the same rules used by psql's \d commands (see [Шаблоны]), so multiple databases can also be excluded by writing wildcard characters in the pattern. When using wildcards, be careful to quote the pattern if needed to prevent shell wildcard expansion.

--extra-float-digits=ndigits
Use the specified value of extra_float_digits when dumping floating-point data, instead of the maximum available precision. Routine dumps made for backup purposes should not use this option.

--if-exists
Use DROP ... IF EXISTS commands to drop objects in --clean mode. This suppresses “does not exist” errors that might otherwise be reported. This option is not valid unless --clean is also specified.

--inserts
Dump data as INSERT commands (rather than COPY). This will make restoration very slow; it is mainly useful for making dumps that can be loaded into non-QHB databases. Note that the restore might fail altogether if you have rearranged column order. The --column-inserts option is safer, though even slower.

--load-via-partition-root
When dumping data for a table partition, make the COPY or INSERT statements target the root of the partitioning hierarchy that contains it, rather than the partition itself. This causes the appropriate partition to be re-determined for each row when the data is loaded. This may be useful when restoring data on a server where rows do not always fall into the same partitions as they did on the original server. That could happen, for example, if the partitioning column is of type text and the two systems have different definitions of the collation used to sort the partitioning column.

--lock-wait-timeout=timeout
Do not wait forever to acquire shared table locks at the beginning of the dump. Instead, fail if unable to lock a table within the specified timeout. The timeout may be specified in any of the formats accepted by SET statement_timeout.

--no-comments
Do not dump comments.

--no-publications
Do not dump publications.

--no-role-passwords
Do not dump passwords for roles. When restored, roles will have a null password, and password authentication will always fail until the password is set. Since password values aren't needed when this option is specified, the role information is read from the catalog view pg_roles instead of pg_authid. Therefore, this option also helps if access to pg_authid is restricted by some security policy.

--no-security-labels
Do not dump security labels.

--no-subscriptions
Do not dump subscriptions.

--no-sync
By default, qhb_dumpall will wait for all files to be written safely to disk. This option causes qhb_dumpall to return without waiting, which is faster, but means that a subsequent operating system crash can leave the dump corrupt. Generally, this option is useful for testing but should not be used when dumping data from production installation.

--no-table-access-method
Do not output commands to select table access methods. With this option, all objects will be created with whichever table access method is the default during restore.

--no-tablespaces
Do not output commands to create tablespaces nor select tablespaces for objects. With this option, all objects will be created in whichever tablespace is the default during restore.

--no-toast-compression
Do not output commands to set TOAST compression methods. With this option, all columns will be restored with the default compression setting.

--no-unlogged-table-data
Do not dump the contents of unlogged tables. This option has no effect on whether or not the table definitions (schema) are dumped; it only suppresses dumping the table data.

--on-conflict-do-nothing
Add ON CONFLICT DO NOTHING to INSERT commands. This option is not valid unless --inserts or --column-inserts is also specified.

--quote-all-identifiers
Force quoting of all identifiers. This option is recommended when dumping a database from a server whose QHB, major version is different from qhb_dumpall's, or when the output is intended to be loaded into a server of a different major version. By default, qhb_dumpall quotes only identifiers that are reserved words in its own major version. This sometimes results in compatibility issues when dealing with servers of other versions that may have slightly different sets of reserved words. Using --quote-all-identifiers prevents such issues, at the price of a harder-to-read dump script.

--rows-per-insert=nrows
Dump data as INSERT commands (rather than COPY). Controls the maximum number of rows per INSERT command. The value specified must be a number greater than zero. Any error during restoring will cause only rows that are part of the problematic INSERT to be lost, rather than the entire table contents.

--use-set-session-authorization
Output SQL-standard SET SESSION AUTHORIZATION commands instead of ALTER OWNER commands to determine object ownership. This makes the dump more standards compatible, but depending on the history of the objects in the dump, might not restore properly.

-?
--help
Show help about qhb_dumpall command line arguments, and exit.

The following command-line options control the database connection parameters.

-d connstr
--dbname=connstr
Specifies parameters used to connect to the server, as a connection string; these will override any conflicting command line options.
The option is called --dbname for consistency with other client applications, but because qhb_dumpall needs to connect to many databases, the database name in the connection string will be ignored. Use the -l option to specify the name of the database used for the initial connection, which will dump global objects and discover what other databases should be dumped.

-h host
--host=host
Specifies the host name of the machine on which the server is running. If the value begins with a slash, it is used as the directory for the Unix domain socket. The default is taken from the PGHOST environment variable, if set, else a Unix domain socket connection is attempted.

-l dbname
--database=dbname
Specifies the name of the database to connect to for dumping global objects and discovering what other databases should be dumped. If not specified, the qhb database will be used, and if that does not exist, template1 will be used.

-p port
--port=port
Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections. Defaults to the PGPORT environment variable, if set, or a compiled-in default.

-U username
--username=username
User name to connect as.

-w
--no-password
Never issue a password prompt. If the server requires password authentication and a password is not available by other means such as a .pgpass file, the connection attempt will fail. This option can be useful in batch jobs and scripts where no user is present to enter a password.

-W
--password
Force qhb_dumpall to prompt for a password before connecting to a database.
This option is never essential, since qhb_dumpall will automatically prompt for a password if the server demands password authentication. However, qhb_dumpall will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing -W to avoid the extra connection attempt.
Note that the password prompt will occur again for each database to be dumped. Usually, it's better to set up a ~/.pgpass file than to rely on manual password entry.

--role=rolename
Specifies a role name to be used to create the dump. This option causes qhb_dumpall to issue a SET ROLE rolename command after connecting to the database. It is useful when the authenticated user (specified by -U) lacks privileges needed by qhb_dumpall, but can switch to a role with the required rights. Some installations have a policy against logging in directly as a superuser, and use of this option allows dumps to be made without violating the policy.

Environment

PGHOST
PGOPTIONS
PGPORT
PGUSER
Default connection parameters

PG_COLOR
Specifies whether to use color in diagnostic messages. Possible values are always, auto and never.

This utility, like most other QHB utilities, also uses the environment variables supported by libpq (see Section Environment Variables).

Notes

Since qhb_dumpall calls qhb_dump internally, some diagnostic messages will refer to qhb_dump.

The --clean option can be useful even when your intention is to restore the dump script into a fresh cluster. Use of --clean authorizes the script to drop and re-create the built-in qhb and template1 databases, ensuring that those databases will retain the same properties (for instance, locale and encoding) that they had in the source cluster. Without the option, those databases will retain their existing database-level properties, as well as any pre-existing contents.

Once restored, it is wise to run ANALYZE on each database so the optimizer has useful statistics. You can also run vacuumdb -a -z to analyze all databases.

The dump script should not be expected to run completely without errors. In particular, because the script will issue CREATE ROLE for every role existing in the source cluster, it is certain to get a “role already exists” error for the bootstrap superuser, unless the destination cluster was initialized with a different bootstrap superuser name. This error is harmless and should be ignored. Use of the --clean option is likely to produce additional harmless error messages about non-existent objects, although you can minimize those by adding --if-exists.

qhb_dumpall requires all needed tablespace directories to exist before the restore; otherwise, database creation will fail for databases in non-default locations.

Examples

To dump all databases:

$ qhb_dumpall > db.out

To restore database(s) from this file, you can use:

$ psql -f db.out qhb

It is not important to which database you connect here since the script file created by qhb_dumpall will contain the appropriate commands to create and connect to the saved databases. An exception is that if you specified --clean, you must connect to the qhb database initially; the script will attempt to drop other databases immediately, and that will fail for the database you are connected to.