Remove "convert 'blah' using conversion_name" facility, because if it

produces text it is an encoding hole and if not it's incompatible
with the spec, whatever the spec means (which we're not sure about anyway).

doc/src/sgml/func.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.397 2007/09/19 03:13:57 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.398 2007/09/24 01:29:27 adunstan Exp $ -->
 
  <chapter id="functions">
   <title>Functions and Operators</title>
@@ -1022,9 +1022,6 @@
    <indexterm>
     <primary>char_length</primary>
    </indexterm>
-   <indexterm>
-    <primary>convert</primary>
-   </indexterm>
    <indexterm>
     <primary>lower</primary>
    </indexterm>
@@ -1119,22 +1116,6 @@
        <entry><literal>4</literal></entry>
       </row>
 
-      <row>
-       <entry><literal><function>convert</function>(<parameter>string</parameter>
-       using <parameter>conversion_name</parameter>)</literal></entry>
-       <entry><type>bytea</type></entry>
-       <entry>
-        Change encoding using specified conversion name.  Conversions
-        can be defined by <command>CREATE CONVERSION</command>.  Also
-        there are some pre-defined conversion names. See <xref
-        linkend="conversion-names"> for available conversion
-        names. The <parameter>string</parameter> must be valid in the
-        source encoding.
-       </entry>
-       <entry><literal>convert('PostgreSQL' using iso_8859_1_to_utf8)</literal></entry>
-       <entry><literal>'PostgreSQL'</literal> in UTF8 (Unicode, 8-bit) encoding</entry>
-      </row>
-
       <row>
        <entry><literal><function>lower</function>(<parameter>string</parameter>)</literal></entry>
        <entry><type>text</type></entry>
@@ -1245,6 +1226,9 @@
    <indexterm>
     <primary>chr</primary>
    </indexterm>
+   <indexterm>
+    <primary>convert</primary>
+   </indexterm>
    <indexterm>
     <primary>convert_from</primary>
    </indexterm>
@@ -1374,6 +1358,9 @@
         original encoding is specified by
         <parameter>src_encoding</parameter>. The
         <parameter>string</parameter> must be valid in this encoding.
+        Conversions can be defined by <command>CREATE CONVERSION</command>.  
+        Also there are some pre-defined conversions. See <xref
+        linkend="conversion-names"> for available conversions.
        </entry>
        <entry><literal>convert( 'text_in_utf8', 'UTF8', 'LATIN1')</literal></entry>
        <entry><literal>text_in_utf8</literal> represented in ISO 8859-1 encoding</entry>

doc/src/sgml/ref/create_conversion.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_conversion.sgml,v 1.19 2007/01/31 23:26:03 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/create_conversion.sgml,v 1.20 2007/09/24 01:29:28 adunstan Exp $ -->
 
 <refentry id="SQL-CREATECONVERSION">
  <refmeta>
@@ -27,9 +27,7 @@ CREATE [ DEFAULT ] CONVERSION <replaceable>name</replaceable>
 
   <para>
    <command>CREATE CONVERSION</command> defines a new conversion between
-   character set encodings.  Conversion names can be used in the
-   <function>convert</function> function
-   to specify a particular encoding conversion.  Also, conversions that
+   character set encodings.  Also, conversions that
    are marked <literal>DEFAULT</> can be used for automatic encoding
    conversion between
    client and server. For this purpose, two conversions, from encoding A to

src/backend/catalog/pg_conversion.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/pg_conversion.c,v 1.37 2007/09/18 17:41:17 adunstan Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/pg_conversion.c,v 1.38 2007/09/24 01:29:28 adunstan Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -276,76 +276,3 @@ FindConversion(const char *conname, Oid connamespace)
 	return conoid;
 }
 
-/*
- * Execute SQL99's CONVERT function.
- *
- * CONVERT <left paren> <character value expression>
- * USING <form-of-use conversion name> <right paren>
- *
- * BYTEA convert_using(TEXT string, TEXT conversion_name)
- *
- * bytea is returned so we don't give a value that is
- * not valid in the database encoding.
- */
-Datum
-pg_convert_using(PG_FUNCTION_ARGS)
-{
-	text	   *string = PG_GETARG_TEXT_P(0);
-	text	   *conv_name = PG_GETARG_TEXT_P(1);
-	text	   *retval;
-	List	   *parsed_name;
-	Oid			convoid;
-	HeapTuple	tuple;
-	Form_pg_conversion body;
-	char	   *str;
-	char	   *result;
-	int			len;
-
-	/* Convert input string to null-terminated form */
-	len = VARSIZE(string) - VARHDRSZ;
-	str = palloc(len + 1);
-	memcpy(str, VARDATA(string), len);
-	*(str + len) = '\0';
-
-	/* Look up the conversion name */
-	parsed_name = textToQualifiedNameList(conv_name);
-	convoid = FindConversionByName(parsed_name);
-	if (!OidIsValid(convoid))
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_OBJECT),
-				 errmsg("conversion \"%s\" does not exist",
-						NameListToString(parsed_name))));
-
-	tuple = SearchSysCache(CONVOID,
-						   ObjectIdGetDatum(convoid),
-						   0, 0, 0);
-	if (!HeapTupleIsValid(tuple))
-		elog(ERROR, "cache lookup failed for conversion %u", convoid);
-	body = (Form_pg_conversion) GETSTRUCT(tuple);
-
-	/* Temporary result area should be more than big enough */
-	result = palloc(len * 4 + 1);
-
-	OidFunctionCall5(body->conproc,
-					 Int32GetDatum(body->conforencoding),
-					 Int32GetDatum(body->contoencoding),
-					 CStringGetDatum(str),
-					 CStringGetDatum(result),
-					 Int32GetDatum(len));
-
-	ReleaseSysCache(tuple);
-
-	/*
-	 * build text result structure. we cannot use textin() here, since textin
-	 * assumes that input string encoding is same as database encoding.
-	 */
-	len = strlen(result) + VARHDRSZ;
-	retval = palloc(len);
-	SET_VARSIZE(retval, len);
-	memcpy(VARDATA(retval), result, len - VARHDRSZ);
-
-	pfree(result);
-	pfree(str);
-
-	PG_RETURN_BYTEA_P(retval);
-}

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.602 2007/09/03 18:46:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.603 2007/09/24 01:29:28 adunstan Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -377,7 +377,7 @@ static Node *makeXmlExpr(XmlExprOp op, char *name, List *named_args, List *args)
 	CHARACTER CHARACTERISTICS CHECK CHECKPOINT CLASS CLOSE
 	CLUSTER COALESCE COLLATE COLUMN COMMENT COMMIT
 	COMMITTED CONCURRENTLY CONFIGURATION CONNECTION CONSTRAINT CONSTRAINTS
-	CONTENT_P CONVERSION_P CONVERT COPY COST CREATE CREATEDB
+	CONTENT_P CONVERSION_P COPY COST CREATE CREATEDB
 	CREATEROLE CREATEUSER CROSS CSV CURRENT_P CURRENT_DATE CURRENT_ROLE
 	CURRENT_TIME CURRENT_TIMESTAMP CURRENT_USER CURSOR CYCLE
 
@@ -8218,31 +8218,6 @@ func_expr:	func_name '(' ')'
 					n->location = @1;
 					$$ = (Node *)n;
 				}
-			| CONVERT '(' a_expr USING any_name ')'
-				{
-					FuncCall *n = makeNode(FuncCall);
-					A_Const *c = makeNode(A_Const);
-
-					c->val.type = T_String;
-					c->val.val.str = NameListToQuotedString($5);
-
-					n->funcname = SystemFuncName("convert_using");
-					n->args = list_make2($3, c);
-					n->agg_star = FALSE;
-					n->agg_distinct = FALSE;
-					n->location = @1;
-					$$ = (Node *)n;
-				}
-			| CONVERT '(' expr_list ')'
-				{
-					FuncCall *n = makeNode(FuncCall);
-					n->funcname = SystemFuncName("convert");
-					n->args = $3;
-					n->agg_star = FALSE;
-					n->agg_distinct = FALSE;
-					n->location = @1;
-					$$ = (Node *)n;
-				}
 			| NULLIF '(' a_expr ',' a_expr ')'
 				{
 					$$ = (Node *) makeSimpleA_Expr(AEXPR_NULLIF, "=", $3, $5, @1);
@@ -9291,7 +9266,6 @@ col_name_keyword:
 			| CHAR_P
 			| CHARACTER
 			| COALESCE
-			| CONVERT
 			| DEC
 			| DECIMAL_P
 			| EXISTS

src/backend/parser/keywords.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/keywords.c,v 1.191 2007/08/21 15:13:42 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/keywords.c,v 1.192 2007/09/24 01:29:29 adunstan Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -93,7 +93,6 @@ static const ScanKeyword ScanKeywords[] = {
 	{"constraints", CONSTRAINTS, UNRESERVED_KEYWORD},
 	{"content", CONTENT_P, UNRESERVED_KEYWORD},
 	{"conversion", CONVERSION_P, UNRESERVED_KEYWORD},
-	{"convert", CONVERT, COL_NAME_KEYWORD},
 	{"copy", COPY, UNRESERVED_KEYWORD},
 	{"cost", COST, UNRESERVED_KEYWORD},
 	{"create", CREATE, RESERVED_KEYWORD},

src/include/catalog/pg_proc.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.471 2007/09/20 17:56:32 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.472 2007/09/24 01:29:29 adunstan Exp $
  *
  * NOTES
  *	  The script catalog/genbki.sh reads this file and generates .bki
@@ -2244,9 +2244,6 @@ DESCR("convert string with specified destination encoding name");
 DATA(insert OID = 1813 (  convert		   PGNSP PGUID 12 1 0 f f t f s 3 17 "17 19 19" _null_ _null_ _null_ pg_convert - _null_ _null_ ));
 DESCR("convert string with specified encoding names");
 
-DATA(insert OID = 1619 (  convert_using    PGNSP PGUID 12 1 0 f f t f s 2 17 "25 25" _null_ _null_ _null_ pg_convert_using - _null_ _null_ ));
-DESCR("convert string with specified conversion name");
-
 DATA(insert OID = 1264 (  pg_char_to_encoding	   PGNSP PGUID 12 1 0 f f t f s 1 23 "19" _null_ _null_ _null_	PG_char_to_encoding - _null_ _null_ ));
 DESCR("convert encoding name to encoding id");
 

src/include/utils/builtins.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.303 2007/09/18 17:41:17 adunstan Exp $
+ * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.304 2007/09/24 01:29:30 adunstan Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -941,9 +941,6 @@ extern Datum pg_advisory_unlock_all(PG_FUNCTION_ARGS);
 /* access/transam/twophase.c */
 extern Datum pg_prepared_xact(PG_FUNCTION_ARGS);
 
-/* catalog/pg_conversion.c */
-extern Datum pg_convert_using(PG_FUNCTION_ARGS);
-
 /* commands/prepare.c */
 extern Datum pg_prepared_statement(PG_FUNCTION_ARGS);