diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/postgres-fdw.sgml | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/doc/src/sgml/postgres-fdw.sgml b/doc/src/sgml/postgres-fdw.sgml index 90969f63ca7..468724e94ef 100644 --- a/doc/src/sgml/postgres-fdw.sgml +++ b/doc/src/sgml/postgres-fdw.sgml @@ -1096,7 +1096,10 @@ postgres=# SELECT postgres_fdw_disconnect_all(); <para> <filename>postgres_fdw</filename> can be used with remote servers dating back to <productname>PostgreSQL</productname> 8.3. Read-only capability is available - back to 8.1. A limitation however is that <filename>postgres_fdw</filename> + back to 8.1. + </para> + <para> + A limitation however is that <filename>postgres_fdw</filename> generally assumes that immutable built-in functions and operators are safe to send to the remote server for execution, if they appear in a <literal>WHERE</literal> clause for a foreign table. Thus, a built-in @@ -1108,6 +1111,13 @@ postgres=# SELECT postgres_fdw_disconnect_all(); optimization fence, and placing the problematic function or operator outside the sub-<literal>SELECT</literal>. </para> + <para> + Another limitation is that when executing <command>INSERT</command> + statements with an <literal>ON CONFLICT DO NOTHING</literal> clause on + a foreign table, the remote server must be running + <productname>PostgreSQL</productname> 9.5 or later, + as earlier versions do not support this feature. + </para> </sect2> <sect2 id="postgres-fdw-wait-events"> |