Add LOCALTIME and LOCALTIMESTAMP functions per SQL99 standard.

Remove ODBC-compatible empty parentheses from calls to SQL99 functions
 for which these parentheses do not match the standard.
Update the ODBC driver to ensure compatibility with the ODBC standard
 for these functions (e.g. CURRENT_TIMESTAMP, CURRENT_USER, etc).
Include a new appendix in the User's Guide which lists the labeled features
 for SQL99 (the labeled features replaced the "basic", "intermediate",
 and "advanced" categories from SQL92). features.sgml does not yet split
 this list into "supported" and "unsupported" lists.

3 files changed, 102 insertions, 13 deletions

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index bfbf23e3df7..b4ff1fcf50f 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.322 2002/06/13 14:16:43 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.323 2002/06/15 03:00:03 thomas Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -259,7 +259,6 @@ static void doNegateFloat(Value *v);
 %type <list>	row_descriptor, row_list, in_expr_nodes
 %type <node>	row_expr
 %type <node>	case_expr, case_arg, when_clause, case_default
-%type <boolean>	opt_empty_parentheses
 %type <list>	when_clause_list
 %type <ival>	sub_type
 %type <list>	OptCreateAs, CreateAsList
@@ -347,7 +346,7 @@ static void doNegateFloat(Value *v);
 	KEY,
 
 	LANCOMPILER, LANGUAGE, LEADING, LEFT, LEVEL, LIKE, LIMIT, LISTEN,
-	LOAD, LOCAL, LOCATION, LOCK_P,
+	LOAD, LOCAL, LOCALTIME, LOCALTIMESTAMP, LOCATION, LOCK_P,
 
 	MATCH, MAXVALUE, MINUTE_P, MINVALUE, MODE, MONTH_P, MOVE,
 
@@ -5461,7 +5460,7 @@ c_expr:  columnref
 					n->agg_distinct = FALSE;
 					$$ = (Node *)n;
 				}
-		| CURRENT_DATE opt_empty_parentheses
+		| CURRENT_DATE
 				{
 					/*
 					 * Translate as "'now'::text::date".
@@ -5487,7 +5486,7 @@ c_expr:  columnref
 
 					$$ = (Node *)makeTypeCast((Node *)s, d);
 				}
-		| CURRENT_TIME opt_empty_parentheses
+		| CURRENT_TIME
 				{
 					/*
 					 * Translate as "'now'::text::timetz".
@@ -5530,7 +5529,7 @@ c_expr:  columnref
 
 					$$ = (Node *)makeTypeCast((Node *)s, d);
 				}
-		| CURRENT_TIMESTAMP opt_empty_parentheses
+		| CURRENT_TIMESTAMP
 				{
 					/*
 					 * Translate as "'now'::text::timestamptz".
@@ -5574,7 +5573,94 @@ c_expr:  columnref
 
 					$$ = (Node *)makeTypeCast((Node *)s, d);
 				}
-		| CURRENT_USER opt_empty_parentheses
+		| LOCALTIME
+				{
+					/*
+					 * Translate as "'now'::text::time".
+					 * See comments for CURRENT_DATE.
+					 */
+					A_Const *s = makeNode(A_Const);
+					TypeName *d;
+
+					s->val.type = T_String;
+					s->val.val.str = "now";
+					s->typename = SystemTypeName("text");
+
+					d = SystemTypeName("time");
+					/* SQL99 mandates a default precision of zero for TIME
+					 * fields in schemas. However, for LOCALTIME
+					 * let's preserve the microsecond precision we
+					 * might see from the system clock. - thomas 2001-12-07
+					 */
+					d->typmod = 6;
+
+					$$ = (Node *)makeTypeCast((Node *)s, d);
+				}
+		| LOCALTIME '(' Iconst ')'
+				{
+					/*
+					 * Translate as "'now'::text::time(n)".
+					 * See comments for CURRENT_DATE.
+					 */
+					A_Const *s = makeNode(A_Const);
+					TypeName *d;
+
+					s->val.type = T_String;
+					s->val.val.str = "now";
+					s->typename = SystemTypeName("text");
+					d = SystemTypeName("time");
+					if (($3 < 0) || ($3 > MAX_TIME_PRECISION))
+						elog(ERROR, "LOCALTIME(%d) precision must be between %d and %d",
+							 $3, 0, MAX_TIME_PRECISION);
+					d->typmod = $3;
+
+					$$ = (Node *)makeTypeCast((Node *)s, d);
+				}
+		| LOCALTIMESTAMP
+				{
+					/*
+					 * Translate as "'now'::text::timestamp".
+					 * See comments for CURRENT_DATE.
+					 */
+					A_Const *s = makeNode(A_Const);
+					TypeName *d;
+
+					s->val.type = T_String;
+					s->val.val.str = "now";
+					s->typename = SystemTypeName("text");
+
+					d = SystemTypeName("timestamp");
+					/* SQL99 mandates a default precision of 6 for timestamp.
+					 * Also, that is about as precise as we will get since
+					 * we are using a microsecond time interface.
+					 * - thomas 2001-12-07
+					 */
+					d->typmod = 6;
+
+					$$ = (Node *)makeTypeCast((Node *)s, d);
+				}
+		| LOCALTIMESTAMP '(' Iconst ')'
+				{
+					/*
+					 * Translate as "'now'::text::timestamp(n)".
+					 * See comments for CURRENT_DATE.
+					 */
+					A_Const *s = makeNode(A_Const);
+					TypeName *d;
+
+					s->val.type = T_String;
+					s->val.val.str = "now";
+					s->typename = SystemTypeName("text");
+
+					d = SystemTypeName("timestamp");
+					if (($3 < 0) || ($3 > MAX_TIMESTAMP_PRECISION))
+						elog(ERROR, "LOCALTIMESTAMP(%d) precision must be between %d and %d",
+							 $3, 0, MAX_TIMESTAMP_PRECISION);
+					d->typmod = $3;
+
+					$$ = (Node *)makeTypeCast((Node *)s, d);
+				}
+		| CURRENT_USER
 				{
 					FuncCall *n = makeNode(FuncCall);
 					n->funcname = SystemFuncName("current_user");
@@ -5583,7 +5669,7 @@ c_expr:  columnref
 					n->agg_distinct = FALSE;
 					$$ = (Node *)n;
 				}
-		| SESSION_USER opt_empty_parentheses
+		| SESSION_USER
 				{
 					FuncCall *n = makeNode(FuncCall);
 					n->funcname = SystemFuncName("session_user");
@@ -5592,7 +5678,7 @@ c_expr:  columnref
 					n->agg_distinct = FALSE;
 					$$ = (Node *)n;
 				}
-		| USER opt_empty_parentheses
+		| USER
 				{
 					FuncCall *n = makeNode(FuncCall);
 					n->funcname = SystemFuncName("current_user");
@@ -5966,9 +6052,6 @@ attrs:  '.' attr_name
 				{ $$ = lcons(makeString($2), $3); }
 		;
 
-opt_empty_parentheses: '(' ')' { $$ = TRUE; }
-					| /*EMPTY*/ { $$ = TRUE; }
-		;
 
 /*****************************************************************************
  *
@@ -6572,6 +6655,8 @@ reserved_keyword:
 		| INTO
 		| LEADING
 		| LIMIT
+		| LOCALTIME
+		| LOCALTIMESTAMP
 		| NEW
 		| NOT
 		| NULL_P
diff --git a/src/backend/parser/keywords.c b/src/backend/parser/keywords.c
index dca44c448f9..0f441290ea8 100644
--- a/src/backend/parser/keywords.c
+++ b/src/backend/parser/keywords.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.113 2002/06/11 15:41:37 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.114 2002/06/15 03:00:03 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -172,6 +172,8 @@ static const ScanKeyword ScanKeywords[] = {
 	{"listen", LISTEN},
 	{"load", LOAD},
 	{"local", LOCAL},
+	{"localtime", LOCALTIME},
+	{"localtimestamp", LOCALTIMESTAMP},
 	{"location", LOCATION},
 	{"lock", LOCK_P},
 	{"match", MATCH},
diff --git a/src/interfaces/odbc/convert.c b/src/interfaces/odbc/convert.c
index 39a430aff3f..60fdc54f9c3 100644
--- a/src/interfaces/odbc/convert.c
+++ b/src/interfaces/odbc/convert.c
@@ -103,6 +103,8 @@ char	   *mapFuncs[][2] = {
 	{"CURRENT_DATE", "current_date" },
 	{"CURRENT_TIME", "current_time" },
 	{"CURRENT_TIMESTAMP", "current_timestamp" },
+	{"LOCALTIME", "localtime" },
+	{"LOCALTIMESTAMP", "localtimestamp" },
 	{"CURRENT_USER", "cast(current_user as text)" },
 	{"SESSION_USER", "cast(session_user as text)" },
 	{"CURDATE",	 "current_date" },