diff options
Diffstat (limited to 'doc/src/sgml/ref/create_subscription.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_subscription.sgml | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/doc/src/sgml/ref/create_subscription.sgml b/doc/src/sgml/ref/create_subscription.sgml index 51c45f17c7d..9d4b9d4e338 100644 --- a/doc/src/sgml/ref/create_subscription.sgml +++ b/doc/src/sgml/ref/create_subscription.sgml @@ -185,15 +185,25 @@ CREATE SUBSCRIPTION <replaceable class="parameter">subscription_name</replaceabl <variablelist> - <varlistentry> + <varlistentry id="sql-createsubscription-binary" xreflabel="binary"> <term><literal>binary</literal> (<type>boolean</type>)</term> <listitem> <para> - Specifies whether the subscription will request the publisher to - send the data in binary format (as opposed to text). - The default is <literal>false</literal>. - Even when this option is enabled, only data types having - binary send and receive functions will be transferred in binary. + Specifies whether the subscription will request the publisher to send + the data in binary format (as opposed to text). The default is + <literal>false</literal>. Any initial table synchronization copy + (see <literal>copy_data</literal>) also uses the same format. Binary + format can be faster than the text format, but it is less portable + across machine architectures and <productname>PostgreSQL</productname> + versions. Binary format is very data type specific; for example, it + will not allow copying from a <type>smallint</type> column to an + <type>integer</type> column, even though that would work fine in text + format. Even when this option is enabled, only data types having binary + send and receive functions will be transferred in binary. Note that + the initial synchronization requires all data types to have binary + send and receive functions, otherwise the synchronization will fail + (see <xref linkend="sql-createtype"/> for more about send/receive + functions). </para> <para> @@ -203,6 +213,12 @@ CREATE SUBSCRIPTION <replaceable class="parameter">subscription_name</replaceabl such a case, data transfer will fail, and the <literal>binary</literal> option cannot be used. </para> + + <para> + If the publisher is a <productname>PostgreSQL</productname> version + before 16, then any initial table synchronization will use text format + even if <literal>binary = true</literal>. + </para> </listitem> </varlistentry> |