NAME

       CREATE_SUBSCRIPTION - define a new subscription

SYNOPSIS

       CREATE SUBSCRIPTION subscription_name
           CONNECTION 'conninfo'
           PUBLICATION publication_name [, ...]
           [ WITH ( subscription_parameter [= value] [, ... ] ) ]

DESCRIPTION

       CREATE SUBSCRIPTION adds a new subscription for the current database. The subscription
       name must be distinct from the name of any existing subscription in the database.

       The subscription represents a replication connection to the publisher. As such this
       command does not only add definitions in the local catalogs but also creates a replication
       slot on the publisher.

       A logical replication worker will be started to replicate data for the new subscription at
       the commit of the transaction where this command is run.

       Additional information about subscriptions and logical replication as a whole is available
       at Section 31.2 and Chapter 31.

PARAMETERS

       subscription_name
           The name of the new subscription.

       CONNECTION 'conninfo'
           The connection string to the publisher. For details see Section 34.1.1.

       PUBLICATION publication_name
           Names of the publications on the publisher to subscribe to.

       WITH ( subscription_parameter [= value] [, ... ] )
           This clause specifies optional parameters for a subscription. The following parameters
           are supported:

           copy_data (boolean)
               Specifies whether the existing data in the publications that are being subscribed
               to should be copied once the replication starts. The default is true.

           create_slot (boolean)
               Specifies whether the command should create the replication slot on the publisher.
               The default is true.

           enabled (boolean)
               Specifies whether the subscription should be actively replicating, or whether it
               should be just setup but not started yet. The default is true.

           slot_name (string)
               Name of the replication slot to use. The default behavior is to use the name of
               the subscription for the slot name.

               When slot_name is set to NONE, there will be no replication slot associated with
               the subscription. This can be used if the replication slot will be created later
               manually. Such subscriptions must also have both enabled and create_slot set to
               false.

           synchronous_commit (enum)
               The value of this parameter overrides the synchronous_commit setting within this
               subscription's apply worker processes. The default value is off.

               It is safe to use off for logical replication: If the subscriber loses
               transactions because of missing synchronization, the data will be sent again from
               the publisher.

               A different setting might be appropriate when doing synchronous logical
               replication. The logical replication workers report the positions of writes and
               flushes to the publisher, and when using synchronous replication, the publisher
               will wait for the actual flush. This means that setting synchronous_commit for the
               subscriber to off when the subscription is used for synchronous replication might
               increase the latency for COMMIT on the publisher. In this scenario, it can be
               advantageous to set synchronous_commit to local or higher.

           binary (boolean)
               Specifies whether the subscription will request the publisher to send the data in
               binary format (as opposed to text). The default is false. Even when this option is
               enabled, only data types that have binary send and receive functions will be
               transferred in binary.

               When doing cross-version replication, it could happen that the publisher has a
               binary send function for some data type, but the subscriber lacks a binary receive
               function for the type. In such a case, data transfer will fail, and the binary
               option cannot be used.

           connect (boolean)
               Specifies whether the CREATE SUBSCRIPTION should connect to the publisher at all.
               Setting this to false will change default values of enabled, create_slot and
               copy_data to false.

               It is not allowed to combine connect set to false and enabled, create_slot, or
               copy_data set to true.

               Since no connection is made when this option is set to false, the tables are not
               subscribed, and so after you enable the subscription nothing will be replicated.
               It is required to run ALTER SUBSCRIPTION ... REFRESH PUBLICATION in order for
               tables to be subscribed.

           streaming (boolean)
               Specifies whether streaming of in-progress transactions should be enabled for this
               subscription. By default, all transactions are fully decoded on the publisher, and
               only then sent to the subscriber as a whole.

NOTES

       See Section 31.7 for details on how to configure access control between the subscription
       and the publication instance.

       When creating a replication slot (the default behavior), CREATE SUBSCRIPTION cannot be
       executed inside a transaction block.

       Creating a subscription that connects to the same database cluster (for example, to
       replicate between databases in the same cluster or to replicate within the same database)
       will only succeed if the replication slot is not created as part of the same command.
       Otherwise, the CREATE SUBSCRIPTION call will hang. To make this work, create the
       replication slot separately (using the function pg_create_logical_replication_slot with
       the plugin name pgoutput) and create the subscription using the parameter create_slot =
       false. This is an implementation restriction that might be lifted in a future release.

EXAMPLES

       Create a subscription to a remote server that replicates tables in the publications
       mypublication and insert_only and starts replicating immediately on commit:

           CREATE SUBSCRIPTION mysub
                    CONNECTION 'host=192.168.1.50 port=5432 user=foo dbname=foodb'
                   PUBLICATION mypublication, insert_only;

       Create a subscription to a remote server that replicates tables in the insert_only
       publication and does not start replicating until enabled at a later time.

           CREATE SUBSCRIPTION mysub
                    CONNECTION 'host=192.168.1.50 port=5432 user=foo dbname=foodb'
                   PUBLICATION insert_only
                          WITH (enabled = false);

COMPATIBILITY

       CREATE SUBSCRIPTION is a PostgreSQL extension.

SEE ALSO

       ALTER SUBSCRIPTION (ALTER_SUBSCRIPTION(7)), DROP SUBSCRIPTION (DROP_SUBSCRIPTION(7)),
       CREATE PUBLICATION (CREATE_PUBLICATION(7)), ALTER PUBLICATION (ALTER_PUBLICATION(7))