Add ENCODING option to COPY TO/FROM and file_fdw.

File encodings can be specified separately from client encoding.
If not specified, client encoding is used for backward compatibility.

Cases when the encoding doesn't match client encoding are slower
than matched cases because we don't have conversion procs for other
encodings. Performance improvement would be be a future work.

Original patch by Hitoshi Harada, and modified by me.

2 files changed, 28 insertions, 3 deletions

diff --git a/doc/src/sgml/file-fdw.sgml b/doc/src/sgml/file-fdw.sgml
index e2921667184..003c415b43a 100644
--- a/doc/src/sgml/file-fdw.sgml
+++ b/doc/src/sgml/file-fdw.sgml
@@ -97,6 +97,17 @@
    </listitem>
   </varlistentry>
 
+  <varlistentry>
+   <term><literal>encoding</literal></term>
+
+   <listitem>
+    <para>
+     Specifies the file's encoding.
+     the same as <command>COPY</>'s <literal>ENCODING</literal> option.
+    </para>
+   </listitem>
+  </varlistentry>
+
  </variablelist>
 
  <para>
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml
index 38424ad04b9..6429a4ef0d7 100644
--- a/doc/src/sgml/ref/copy.sgml
+++ b/doc/src/sgml/ref/copy.sgml
@@ -40,7 +40,8 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
     QUOTE '<replaceable class="parameter">quote_character</replaceable>'
     ESCAPE '<replaceable class="parameter">escape_character</replaceable>'
     FORCE_QUOTE { ( <replaceable class="parameter">column</replaceable> [, ...] ) | * }
-    FORCE_NOT_NULL ( <replaceable class="parameter">column</replaceable> [, ...] )
+    FORCE_NOT_NULL ( <replaceable class="parameter">column</replaceable> [, ...] ) |
+    ENCODING '<replaceable class="parameter">encoding_name</replaceable>'
 </synopsis>
  </refsynopsisdiv>
 
@@ -282,6 +283,18 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><literal>ENCODING</></term>
+    <listitem>
+     <para>
+      Specifies that the file is encoded in the <replaceable
+      class="parameter">encoding_name</replaceable>.  If this option is
+      omitted, the current client encoding is used. See the Notes below
+      for more details.
+     </para>
+    </listitem>
+   </varlistentry>
+
   </variablelist>
  </refsect1>
 
@@ -377,8 +390,9 @@ COPY <replaceable class="parameter">count</replaceable>
    </para>
 
    <para>
-    Input data is interpreted according to the current client encoding,
-    and output data is encoded in the current client encoding, even
+    Input data is interpreted according to <literal>ENCODING</literal>
+    option or the current client encoding, and output data is encoded
+    in <literal>ENCODING</literal> or the current client encoding, even
     if the data does not pass through the client but is read from or
     written to a file directly by the server.
    </para>