Adjust the parser to accept the typename syntax INTERVAL ... SECOND(n)

and the literal syntax INTERVAL 'string' ... SECOND(n), as required by the
SQL standard.  Our old syntax put (n) directly after INTERVAL, which was
a mistake, but will still be accepted for backward compatibility as well
as symmetry with the TIMESTAMP cases.

Change intervaltypmodout to show it in the spec's way, too.  (This could
potentially affect clients, if there are any that analyze the typmod of an
INTERVAL in any detail.)

Also fix interval input to handle 'min:sec.frac' properly; I had overlooked
this case in my previous patch.

Document the use of the interval fields qualifier, which up to now we had
never mentioned in the docs.  (I think the omission was intentional because
it didn't work per spec; but it does now, or at least close enough to be
credible.)

1 files changed, 114 insertions, 42 deletions

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 5c716dd8f22..ecbd55d1302 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.622 2008/09/02 20:37:54 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.623 2008/09/11 15:27:30 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -292,7 +292,7 @@ static TypeName *TableFuncTypeName(List *columns);
 
 %type <list>	extract_list overlay_list position_list
 %type <list>	substr_list trim_list
-%type <ival>	opt_interval
+%type <list>	opt_interval interval_second
 %type <node>	overlay_placing substr_from substr_for
 
 %type <boolean> opt_instead opt_analyze
@@ -1222,28 +1222,39 @@ zone_value:
 			| ConstInterval Sconst opt_interval
 				{
 					TypeName *t = $1;
-					if ($3 != INTERVAL_FULL_RANGE)
+					if ($3 != NIL)
 					{
-						if (($3 & ~(INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE))) != 0)
+						A_Const *n = (A_Const *) linitial($3);
+						if ((n->val.val.ival & ~(INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE))) != 0)
 							ereport(ERROR,
 									(errcode(ERRCODE_SYNTAX_ERROR),
 									 errmsg("time zone interval must be HOUR or HOUR TO MINUTE"),
 									 scanner_errposition(@3)));
-						t->typmods = list_make1(makeIntConst($3, @3));
 					}
+					t->typmods = $3;
 					$$ = makeStringConstCast($2, @2, t);
 				}
 			| ConstInterval '(' Iconst ')' Sconst opt_interval
 				{
 					TypeName *t = $1;
-					if (($6 != INTERVAL_FULL_RANGE)
-						&& (($6 & ~(INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE))) != 0))
-						ereport(ERROR,
-								(errcode(ERRCODE_SYNTAX_ERROR),
-								 errmsg("time zone interval must be HOUR or HOUR TO MINUTE"),
-								 scanner_errposition(@6)));
-					t->typmods = list_make2(makeIntConst($6, @6),
-											makeIntConst($3, @3));
+					if ($6 != NIL)
+					{
+						A_Const *n = (A_Const *) linitial($6);
+						if ((n->val.val.ival & ~(INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE))) != 0)
+							ereport(ERROR,
+									(errcode(ERRCODE_SYNTAX_ERROR),
+									 errmsg("time zone interval must be HOUR or HOUR TO MINUTE"),
+									 scanner_errposition(@6)));
+						if (list_length($6) != 1)
+							ereport(ERROR,
+									(errcode(ERRCODE_SYNTAX_ERROR),
+									 errmsg("interval precision specified twice"),
+									 scanner_errposition(@1)));
+						t->typmods = lappend($6, makeIntConst($3, @3));
+					}
+					else
+						t->typmods = list_make2(makeIntConst(INTERVAL_FULL_RANGE, -1),
+												makeIntConst($3, @3));
 					$$ = makeStringConstCast($5, @5, t);
 				}
 			| NumericOnly							{ $$ = makeAConst($1, @1); }
@@ -6983,14 +6994,23 @@ SimpleTypename:
 			| ConstInterval opt_interval
 				{
 					$$ = $1;
-					if ($2 != INTERVAL_FULL_RANGE)
-						$$->typmods = list_make1(makeIntConst($2, @2));
+					$$->typmods = $2;
 				}
 			| ConstInterval '(' Iconst ')' opt_interval
 				{
 					$$ = $1;
-					$$->typmods = list_make2(makeIntConst($5, @5),
-											 makeIntConst($3, @3));
+					if ($5 != NIL)
+					{
+						if (list_length($5) != 1)
+							ereport(ERROR,
+									(errcode(ERRCODE_SYNTAX_ERROR),
+									 errmsg("interval precision specified twice"),
+									 scanner_errposition(@1)));
+						$$->typmods = lappend($5, makeIntConst($3, @3));
+					}
+					else
+						$$->typmods = list_make2(makeIntConst(INTERVAL_FULL_RANGE, -1),
+												 makeIntConst($3, @3));
 				}
 		;
 
@@ -7337,30 +7357,74 @@ opt_timezone:
 		;
 
 opt_interval:
-			YEAR_P									{ $$ = INTERVAL_MASK(YEAR); }
-			| MONTH_P								{ $$ = INTERVAL_MASK(MONTH); }
-			| DAY_P									{ $$ = INTERVAL_MASK(DAY); }
-			| HOUR_P								{ $$ = INTERVAL_MASK(HOUR); }
-			| MINUTE_P								{ $$ = INTERVAL_MASK(MINUTE); }
-			| SECOND_P								{ $$ = INTERVAL_MASK(SECOND); }
+			YEAR_P
+				{ $$ = list_make1(makeIntConst(INTERVAL_MASK(YEAR), @1)); }
+			| MONTH_P
+				{ $$ = list_make1(makeIntConst(INTERVAL_MASK(MONTH), @1)); }
+			| DAY_P
+				{ $$ = list_make1(makeIntConst(INTERVAL_MASK(DAY), @1)); }
+			| HOUR_P
+				{ $$ = list_make1(makeIntConst(INTERVAL_MASK(HOUR), @1)); }
+			| MINUTE_P
+				{ $$ = list_make1(makeIntConst(INTERVAL_MASK(MINUTE), @1)); }
+			| interval_second
+				{ $$ = $1; }
 			| YEAR_P TO MONTH_P
-					{ $$ = INTERVAL_MASK(YEAR) | INTERVAL_MASK(MONTH); }
+				{
+					$$ = list_make1(makeIntConst(INTERVAL_MASK(YEAR) |
+												 INTERVAL_MASK(MONTH), @1));
+				}
 			| DAY_P TO HOUR_P
-					{ $$ = INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR); }
+				{
+					$$ = list_make1(makeIntConst(INTERVAL_MASK(DAY) |
+												 INTERVAL_MASK(HOUR), @1));
+				}
 			| DAY_P TO MINUTE_P
-					{ $$ = INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR)
-						| INTERVAL_MASK(MINUTE); }
-			| DAY_P TO SECOND_P
-					{ $$ = INTERVAL_MASK(DAY) | INTERVAL_MASK(HOUR)
-						| INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND); }
+				{
+					$$ = list_make1(makeIntConst(INTERVAL_MASK(DAY) |
+												 INTERVAL_MASK(HOUR) |
+												 INTERVAL_MASK(MINUTE), @1));
+				}
+			| DAY_P TO interval_second
+				{
+					$$ = $3;
+					linitial($$) = makeIntConst(INTERVAL_MASK(DAY) |
+												INTERVAL_MASK(HOUR) |
+												INTERVAL_MASK(MINUTE) |
+												INTERVAL_MASK(SECOND), @1);
+				}
 			| HOUR_P TO MINUTE_P
-					{ $$ = INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE); }
-			| HOUR_P TO SECOND_P
-					{ $$ = INTERVAL_MASK(HOUR) | INTERVAL_MASK(MINUTE)
-						| INTERVAL_MASK(SECOND); }
-			| MINUTE_P TO SECOND_P
-					{ $$ = INTERVAL_MASK(MINUTE) | INTERVAL_MASK(SECOND); }
-			| /*EMPTY*/								{ $$ = INTERVAL_FULL_RANGE; }
+				{
+					$$ = list_make1(makeIntConst(INTERVAL_MASK(HOUR) |
+												 INTERVAL_MASK(MINUTE), @1));
+				}
+			| HOUR_P TO interval_second
+				{
+					$$ = $3;
+					linitial($$) = makeIntConst(INTERVAL_MASK(HOUR) |
+												INTERVAL_MASK(MINUTE) |
+												INTERVAL_MASK(SECOND), @1);
+				}
+			| MINUTE_P TO interval_second
+				{
+					$$ = $3;
+					linitial($$) = makeIntConst(INTERVAL_MASK(MINUTE) |
+												INTERVAL_MASK(SECOND), @1);
+				}
+			| /*EMPTY*/
+				{ $$ = NIL; }
+		;
+
+interval_second:
+			SECOND_P
+				{
+					$$ = list_make1(makeIntConst(INTERVAL_MASK(SECOND), @1));
+				}
+			| SECOND_P '(' Iconst ')'
+				{
+					$$ = list_make2(makeIntConst(INTERVAL_MASK(SECOND), @1),
+									makeIntConst($3, @3));
+				}
 		;
 
 
@@ -9014,16 +9078,24 @@ AexprConst: Iconst
 			| ConstInterval Sconst opt_interval
 				{
 					TypeName *t = $1;
-					/* precision is not specified, but fields may be... */
-					if ($3 != INTERVAL_FULL_RANGE)
-						t->typmods = list_make1(makeIntConst($3, @3));
+					t->typmods = $3;
 					$$ = makeStringConstCast($2, @2, t);
 				}
 			| ConstInterval '(' Iconst ')' Sconst opt_interval
 				{
 					TypeName *t = $1;
-					t->typmods = list_make2(makeIntConst($6, @6),
-										    makeIntConst($3, @3));
+					if ($6 != NIL)
+					{
+						if (list_length($6) != 1)
+							ereport(ERROR,
+									(errcode(ERRCODE_SYNTAX_ERROR),
+									 errmsg("interval precision specified twice"),
+									 scanner_errposition(@1)));
+						t->typmods = lappend($6, makeIntConst($3, @3));
+					}
+					else
+						t->typmods = list_make2(makeIntConst(INTERVAL_FULL_RANGE, -1),
+												makeIntConst($3, @3));
 					$$ = makeStringConstCast($5, @5, t);
 				}
 			| TRUE_P