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><H1
><A
NAME="SQL-CREATECONVERSION"
></A
>CREATE CONVERSION</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN67839"
></A
><H2
>Name</H2
>CREATE CONVERSION -- define a new encoding conversion</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN67844"
></A
><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>CREATE [ DEFAULT ] CONVERSION <TT
CLASS="REPLACEABLE"
><I
>name</I
></TT
>
FOR <TT
CLASS="REPLACEABLE"
><I
>source_encoding</I
></TT
> TO <TT
CLASS="REPLACEABLE"
><I
>dest_encoding</I
></TT
> FROM <TT
CLASS="REPLACEABLE"
><I
>function_name</I
></TT
></PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SQL-CREATECONVERSION-DESCRIPTION"
></A
><H2
>Description</H2
><P
> <TT
CLASS="COMMAND"
>CREATE CONVERSION</TT
> defines a new conversion between
character set encodings. Also, conversions that
are marked <TT
CLASS="LITERAL"
>DEFAULT</TT
> can be used for automatic encoding
conversion between
client and server. For this purpose, two conversions, from encoding A to
B <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>and</I
></SPAN
> from encoding B to A, must be defined.
</P
><P
> To be able to create a conversion, you must have <TT
CLASS="LITERAL"
>EXECUTE</TT
> privilege
on the function and <TT
CLASS="LITERAL"
>CREATE</TT
> privilege on the destination schema.
</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN67859"
></A
><H2
>Parameters</H2
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>DEFAULT</TT
></DT
><DD
><P
> The <TT
CLASS="LITERAL"
>DEFAULT</TT
> clause indicates that this conversion
is the default for this particular source to destination
encoding. There should be only one default encoding in a schema
for the encoding pair.
</P
></DD
><DT
><TT
CLASS="REPLACEABLE"
><I
>name</I
></TT
></DT
><DD
><P
> The name of the conversion. The conversion name can be
schema-qualified. If it is not, the conversion is defined in the
current schema. The conversion name must be unique within a
schema.
</P
></DD
><DT
><TT
CLASS="REPLACEABLE"
><I
>source_encoding</I
></TT
></DT
><DD
><P
> The source encoding name.
</P
></DD
><DT
><TT
CLASS="REPLACEABLE"
><I
>dest_encoding</I
></TT
></DT
><DD
><P
> The destination encoding name.
</P
></DD
><DT
><TT
CLASS="REPLACEABLE"
><I
>function_name</I
></TT
></DT
><DD
><P
> The function used to perform the conversion. The function name can
be schema-qualified. If it is not, the function will be looked
up in the path.
</P
><P
> The function must have the following signature:
</P><PRE
CLASS="PROGRAMLISTING"
>conv_proc(
integer, -- source encoding ID
integer, -- destination encoding ID
cstring, -- source string (null terminated C string)
internal, -- destination (fill with a null terminated C string)
integer -- source string length
) RETURNS void;</PRE
><P></P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SQL-CREATECONVERSION-NOTES"
></A
><H2
>Notes</H2
><P
> Use <TT
CLASS="COMMAND"
>DROP CONVERSION</TT
> to remove user-defined conversions.
</P
><P
> The privileges required to create a conversion might be changed in a future
release.
</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SQL-CREATECONVERSION-EXAMPLES"
></A
><H2
>Examples</H2
><P
> To create a conversion from encoding <TT
CLASS="LITERAL"
>UTF8</TT
> to
<TT
CLASS="LITERAL"
>LATIN1</TT
> using <CODE
CLASS="FUNCTION"
>myfunc</CODE
>:
</P><PRE
CLASS="PROGRAMLISTING"
>CREATE CONVERSION myconv FOR 'UTF8' TO 'LATIN1' FROM myfunc;</PRE
><P></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SQL-CREATECONVERSION-COMPAT"
></A
><H2
>Compatibility</H2
><P
> <TT
CLASS="COMMAND"
>CREATE CONVERSION</TT
>
is a <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> extension.
There is no <TT
CLASS="COMMAND"
>CREATE CONVERSION</TT
>
statement in the SQL standard, but a <TT
CLASS="COMMAND"
>CREATE TRANSLATION</TT
>
statement that is very similar in purpose and syntax.
</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SQL-CREATECONVERSION-SEEALSO"
></A
><H2
>See Also</H2
><A
HREF="sql-alterconversion.html"
>ALTER CONVERSION</A
>, <A
HREF="sql-createfunction.html"
>CREATE FUNCTION</A
>, <A
HREF="sql-dropconversion.html"
>DROP CONVERSION</A
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