diff options
Diffstat (limited to 'doc/src/sgml/postgres-fdw.sgml')
| -rw-r--r-- | doc/src/sgml/postgres-fdw.sgml | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/doc/src/sgml/postgres-fdw.sgml b/doc/src/sgml/postgres-fdw.sgml index bf95da9721f..41c952fbe32 100644 --- a/doc/src/sgml/postgres-fdw.sgml +++ b/doc/src/sgml/postgres-fdw.sgml @@ -95,8 +95,8 @@ referenced columns of the remote table. Although <filename>postgres_fdw</filename> is currently rather forgiving about performing data type conversions at need, surprising semantic anomalies may arise when types or collations do - not match, due to the remote server interpreting <literal>WHERE</literal> clauses - slightly differently from the local server. + not match, due to the remote server interpreting query conditions + differently from the local server. </para> <para> @@ -537,6 +537,17 @@ OPTIONS (ADD password_required 'false'); need to turn this off if the remote server has a different set of collation names than the local server does, which is likely to be the case if it's running on a different operating system. + If you do so, however, there is a very severe risk that the imported + table columns' collations will not match the underlying data, resulting + in anomalous query behavior. + </para> + + <para> + Even when this parameter is set to <literal>true</literal>, importing + columns whose collation is the remote server's default can be risky. + They will be imported with <literal>COLLATE "default"</literal>, which + will select the local server's default collation, which could be + different. </para> </listitem> </varlistentry> @@ -614,9 +625,9 @@ OPTIONS (ADD password_required 'false'); establishes to foreign servers are kept open in the local session for re-use. </para> - + <variablelist> - + <varlistentry> <term><literal>keep_connections</literal> (<type>boolean</type>)</term> <listitem> @@ -630,7 +641,7 @@ OPTIONS (ADD password_required 'false'); </para> </listitem> </varlistentry> - + </variablelist> </sect3> </sect2> |