fix-VALUES-RTE-typmods-9.6.patch

diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c
index 1e3ecbc..c51fd81 100644
*** a/src/backend/parser/parse_relation.c
--- b/src/backend/parser/parse_relation.c
*************** static void expandTupleDesc(TupleDesc tu
*** 52,57 ****
--- 52,58 ----
  				int rtindex, int sublevels_up,
  				int location, bool include_dropped,
  				List **colnames, List **colvars);
+ static int32 *getValuesTypmods(RangeTblEntry *rte);
  static int	specialAttNum(const char *attname);
  static bool isQueryUsingTempRelation_walker(Node *node, void *context);
  
*************** expandRTE(RangeTblEntry *rte, int rtinde
*** 2157,2165 ****
--- 2158,2179 ----
  			{
  				/* Values RTE */
  				ListCell   *aliasp_item = list_head(rte->eref->colnames);
+ 				int32	   *coltypmods;
  				ListCell   *lcv;
  				ListCell   *lcc;
  
+ 				/*
+ 				 * It's okay to extract column types from the expressions in
+ 				 * the first row, since all rows will have been coerced to the
+ 				 * same types.  Their typmods might not be the same though, so
+ 				 * we potentially need to examine all rows to compute those.
+ 				 * Column collations are pre-computed in values_collations.
+ 				 */
+ 				if (colvars)
+ 					coltypmods = getValuesTypmods(rte);
+ 				else
+ 					coltypmods = NULL;
+ 
  				varattno = 0;
  				forboth(lcv, (List *) linitial(rte->values_lists),
  						lcc, rte->values_collations)
*************** expandRTE(RangeTblEntry *rte, int rtinde
*** 2184,2196 ****
  
  						varnode = makeVar(rtindex, varattno,
  										  exprType(col),
! 										  exprTypmod(col),
  										  colcollation,
  										  sublevels_up);
  						varnode->location = location;
  						*colvars = lappend(*colvars, varnode);
  					}
  				}
  			}
  			break;
  		case RTE_JOIN:
--- 2198,2212 ----
  
  						varnode = makeVar(rtindex, varattno,
  										  exprType(col),
! 										  coltypmods[varattno - 1],
  										  colcollation,
  										  sublevels_up);
  						varnode->location = location;
  						*colvars = lappend(*colvars, varnode);
  					}
  				}
+ 				if (coltypmods)
+ 					pfree(coltypmods);
  			}
  			break;
  		case RTE_JOIN:
*************** expandRTE(RangeTblEntry *rte, int rtinde
*** 2296,2301 ****
--- 2312,2319 ----
  						varnode = makeVar(rtindex, varattno,
  										  coltype, coltypmod, colcoll,
  										  sublevels_up);
+ 						varnode->location = location;
+ 
  						*colvars = lappend(*colvars, varnode);
  					}
  				}
*************** expandTupleDesc(TupleDesc tupdesc, Alias
*** 2413,2418 ****
--- 2431,2504 ----
  }
  
  /*
+  * getValuesTypmods -- expandRTE subroutine
+  *
+  * Identify per-column typmods for the given VALUES RTE.  Returns a
+  * palloc'd array.
+  */
+ static int32 *
+ getValuesTypmods(RangeTblEntry *rte)
+ {
+ 	int32	   *coltypmods;
+ 	List	   *firstrow;
+ 	int			ncolumns,
+ 				nvalid,
+ 				i;
+ 	ListCell   *lc;
+ 
+ 	Assert(rte->values_lists != NIL);
+ 	firstrow = (List *) linitial(rte->values_lists);
+ 	ncolumns = list_length(firstrow);
+ 	coltypmods = (int32 *) palloc(ncolumns * sizeof(int32));
+ 	nvalid = 0;
+ 
+ 	/* Collect the typmods from the first VALUES row */
+ 	i = 0;
+ 	foreach(lc, firstrow)
+ 	{
+ 		Node	   *col = (Node *) lfirst(lc);
+ 
+ 		coltypmods[i] = exprTypmod(col);
+ 		if (coltypmods[i] >= 0)
+ 			nvalid++;
+ 		i++;
+ 	}
+ 
+ 	/*
+ 	 * Scan remaining rows; as soon as we have a non-matching typmod for a
+ 	 * column, reset that typmod to -1.  We can bail out early if all typmods
+ 	 * become -1.
+ 	 */
+ 	if (nvalid > 0)
+ 	{
+ 		for_each_cell(lc, lnext(list_head(rte->values_lists)))
+ 		{
+ 			List	   *thisrow = (List *) lfirst(lc);
+ 			ListCell   *lc2;
+ 
+ 			Assert(list_length(thisrow) == ncolumns);
+ 			i = 0;
+ 			foreach(lc2, thisrow)
+ 			{
+ 				Node	   *col = (Node *) lfirst(lc2);
+ 
+ 				if (coltypmods[i] >= 0 && coltypmods[i] != exprTypmod(col))
+ 				{
+ 					coltypmods[i] = -1;
+ 					nvalid--;
+ 				}
+ 				i++;
+ 			}
+ 
+ 			if (nvalid <= 0)
+ 				break;
+ 		}
+ 	}
+ 
+ 	return coltypmods;
+ }
+ 
+ /*
   * expandRelAttrs -
   *	  Workhorse for "*" expansion: produce a list of targetentries
   *	  for the attributes of the RTE
*************** get_rte_attribute_type(RangeTblEntry *rt
*** 2656,2673 ****
  			break;
  		case RTE_VALUES:
  			{
! 				/* Values RTE --- get type info from first sublist */
! 				/* collation is stored separately, though */
  				List	   *collist = (List *) linitial(rte->values_lists);
  				Node	   *col;
  
  				if (attnum < 1 || attnum > list_length(collist))
  					elog(ERROR, "values list %s does not have attribute %d",
  						 rte->eref->aliasname, attnum);
  				col = (Node *) list_nth(collist, attnum - 1);
  				*vartype = exprType(col);
! 				*vartypmod = exprTypmod(col);
  				*varcollid = list_nth_oid(rte->values_collations, attnum - 1);
  			}
  			break;
  		case RTE_JOIN:
--- 2742,2766 ----
  			break;
  		case RTE_VALUES:
  			{
! 				/*
! 				 * Values RTE --- we can get type info from first sublist, but
! 				 * typmod may require scanning all sublists, and collation is
! 				 * stored separately.  Using getValuesTypmods() is overkill,
! 				 * but this path is taken so seldom for VALUES that it's not
! 				 * worth writing extra code.
! 				 */
  				List	   *collist = (List *) linitial(rte->values_lists);
  				Node	   *col;
+ 				int32	   *coltypmods = getValuesTypmods(rte);
  
  				if (attnum < 1 || attnum > list_length(collist))
  					elog(ERROR, "values list %s does not have attribute %d",
  						 rte->eref->aliasname, attnum);
  				col = (Node *) list_nth(collist, attnum - 1);
  				*vartype = exprType(col);
! 				*vartypmod = coltypmods[attnum - 1];
  				*varcollid = list_nth_oid(rte->values_collations, attnum - 1);
+ 				pfree(coltypmods);
  			}
  			break;
  		case RTE_JOIN:
diff --git a/src/test/regress/expected/create_view.out b/src/test/regress/expected/create_view.out
index 81b4e8d..b1c3cff 100644
*** a/src/test/regress/expected/create_view.out
--- b/src/test/regress/expected/create_view.out
*************** SELECT relname, relkind, reloptions FROM
*** 288,293 ****
--- 288,330 ----
   mysecview4 | v       | {security_barrier=false}
  (4 rows)
  
+ -- This test checks that proper typmods are assigned in a multi-row VALUES
+ CREATE VIEW tt1 AS
+   SELECT * FROM (
+     VALUES
+        ('abc'::varchar(3), '0123456789', 42, 'abcd'::varchar(4)),
+        ('0123456789', 'abc'::varchar(3), 42.12, 'abc'::varchar(4))
+   ) vv(a,b,c,d);
+ \d+ tt1
+                       View "testviewschm2.tt1"
+  Column |         Type         | Modifiers | Storage  | Description 
+ --------+----------------------+-----------+----------+-------------
+  a      | character varying    |           | extended | 
+  b      | character varying    |           | extended | 
+  c      | numeric              |           | main     | 
+  d      | character varying(4) |           | extended | 
+ View definition:
+  SELECT vv.a,
+     vv.b,
+     vv.c,
+     vv.d
+    FROM ( VALUES ('abc'::character varying(3),'0123456789'::character varying,42,'abcd'::character varying(4)), ('0123456789'::character varying,'abc'::character varying(3),42.12,'abc'::character varying(4))) vv(a, b, c, d);
+ 
+ SELECT * FROM tt1;
+      a      |     b      |   c   |  d   
+ ------------+------------+-------+------
+  abc        | 0123456789 |    42 | abcd
+  0123456789 | abc        | 42.12 | abc
+ (2 rows)
+ 
+ SELECT a::varchar(3) FROM tt1;
+   a  
+ -----
+  abc
+  012
+ (2 rows)
+ 
+ DROP VIEW tt1;
  -- Test view decompilation in the face of relation renaming conflicts
  CREATE TABLE tt1 (f1 int, f2 int, f3 text);
  CREATE TABLE tx1 (x1 int, x2 int, x3 text);
diff --git a/src/test/regress/sql/create_view.sql b/src/test/regress/sql/create_view.sql
index 8bed5a5..5fe8b94 100644
*** a/src/test/regress/sql/create_view.sql
--- b/src/test/regress/sql/create_view.sql
*************** SELECT relname, relkind, reloptions FROM
*** 224,229 ****
--- 224,242 ----
                       'mysecview3'::regclass, 'mysecview4'::regclass)
         ORDER BY relname;
  
+ -- This test checks that proper typmods are assigned in a multi-row VALUES
+ 
+ CREATE VIEW tt1 AS
+   SELECT * FROM (
+     VALUES
+        ('abc'::varchar(3), '0123456789', 42, 'abcd'::varchar(4)),
+        ('0123456789', 'abc'::varchar(3), 42.12, 'abc'::varchar(4))
+   ) vv(a,b,c,d);
+ \d+ tt1
+ SELECT * FROM tt1;
+ SELECT a::varchar(3) FROM tt1;
+ DROP VIEW tt1;
+ 
  -- Test view decompilation in the face of relation renaming conflicts
  
  CREATE TABLE tt1 (f1 int, f2 int, f3 text);