database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-08-27 07:42:10 +03:00
Code Activity

Logical replication support for initial data copy

Browse Source 
Add functionality for a new subscription to copy the initial data in the
tables and then sync with the ongoing apply process.

For the copying, add a new internal COPY option to have the COPY source
data provided by a callback function.  The initial data copy works on
the subscriber by receiving COPY data from the publisher and then
providing it locally into a COPY that writes to the destination table.

A WAL receiver can now execute full SQL commands.  This is used here to
obtain information about tables and publications.

Several new options were added to CREATE and ALTER SUBSCRIPTION to
control whether and when initial table syncing happens.

Change pg_dump option --no-create-subscription-slots to
--no-subscription-connect and use the new CREATE SUBSCRIPTION
... NOCONNECT option for that.

Author: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Tested-by: Erik Rijkers <er@xs4all.nl>
This commit is contained in:
Peter Eisentraut
2017-03-23 08:36:36 -04:00
parent 707576b571
commit 7c4f52409a
62 changed files with 2969 additions and 344 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
doc/src/sgml/ref/create_subscription.sgml
View File

@@ -31,6 +31,8 @@ CREATE SUBSCRIPTION <replaceable class="PARAMETER">subscription_name</replaceabl
| ENABLED | DISABLED
| CREATE SLOT | NOCREATE SLOT
| SLOT NAME = <replaceable class="PARAMETER">slot_name</replaceable>
| COPY DATA | NOCOPY DATA
| NOCONNECT
</synopsis>
</refsynopsisdiv>
@@ -132,6 +134,42 @@ CREATE SUBSCRIPTION <replaceable class="PARAMETER">subscription_name</replaceabl
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>COPY DATA</term>
<term>NOCOPY DATA</term>
<listitem>
<para>
Specifies if the existing data in the publications that are being
subscribed to should be copied once the replication starts.
<literal>COPY DATA</literal> is the default.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>NOCONNECT</term>
<listitem>
<para>
Instructs <command>CREATE SUBSCRIPTION</command> to skip the initial
connection to the provider. This will change default values of other
options to <literal>DISABLED</literal>,
<literal>NOCREATE SLOT</literal>, and <literal>NOCOPY DATA</literal>.
</para>
<para>
It's not allowed to combine <literal>NOCONNECT</literal> and
<literal>ENABLED</literal>, <literal>CREATE SLOT</literal>, or
<literal>COPY DATA</literal>.
</para>
<para>
Since no connection is made when this option is specified, the tables
are not subscribed, so after you enable the subscription nothing will
be replicated. It is required to run
<literal>ALTER SUBSCRIPTION ... REFRESH PUBLICATION</> in order for
tables to be subscribed.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>