Fix ruleutils.c's dumping of whole-row Vars in ROW() and VALUES() contexts.

Normally ruleutils prints a whole-row Var as "foo.*".  We already knew that
that doesn't work at top level of a SELECT list, because the parser would
treat the "*" as a directive to expand the reference into separate columns,
not a whole-row Var.  However, Joshua Yanovski points out in bug #13776
that the same thing happens at top level of a ROW() construct; and some
nosing around in the parser shows that the same is true in VALUES().
Hence, apply the same workaround already devised for the SELECT-list case,
namely to add a forced cast to the appropriate rowtype in these cases.
(The alternative of just printing "foo" was rejected because it is
difficult to avoid ambiguity against plain columns named "foo".)

Back-patch to all supported branches.

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 8258463a104454ca758bccf6c76f6fc520c9c807..5bac2f03a6ceceaab3df51a70407abe80c40f268 100644 (file)
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -226,6 +226,8 @@ static void appendContextKeyword(deparse_context *context, const char *str,
                     int indentBefore, int indentAfter, int indentPlus);
 static void get_rule_expr(Node *node, deparse_context *context,
              bool showimplicit);
+static void get_rule_expr_toplevel(Node *node, deparse_context *context,
+                      bool showimplicit);
 static void get_oper_expr(OpExpr *expr, deparse_context *context);
 static void get_func_expr(FuncExpr *expr, deparse_context *context,
              bool showimplicit);
@@ -2762,10 +2764,10 @@ get_values_def(List *values_lists, deparse_context *context)
 
            /*
             * Strip any top-level nodes representing indirection assignments,
-            * then print the result.
+            * then print the result.  Whole-row Vars need special treatment.
             */
-           get_rule_expr(processIndirection(col, context, false),
-                         context, false);
+           get_rule_expr_toplevel(processIndirection(col, context, false),
+                                  context, false);
        }
        appendStringInfoChar(buf, ')');
    }
@@ -3142,7 +3144,8 @@ get_target_list(List *targetList, deparse_context *context,
         * the top level of a SELECT list it's not right (the parser will
         * expand that notation into multiple columns, yielding behavior
         * different from a whole-row Var).  We need to call get_variable
-        * directly so that we can tell it to do the right thing.
+        * directly so that we can tell it to do the right thing, and so that
+        * we can get the attribute name which is the default AS label.
         */
        if (tle->expr && IsA(tle->expr, Var))
        {
@@ -5617,7 +5620,8 @@ get_rule_expr(Node *node, deparse_context *context,
                        !tupdesc->attrs[i]->attisdropped)
                    {
                        appendStringInfoString(buf, sep);
-                       get_rule_expr(e, context, true);
+                       /* Whole-row Vars need special treatment here */
+                       get_rule_expr_toplevel(e, context, true);
                        sep = ", ";
                    }
                    i++;
@@ -5997,6 +6001,27 @@ get_rule_expr(Node *node, deparse_context *context,
    }
 }
 
+/*
+ * get_rule_expr_toplevel      - Parse back a toplevel expression
+ *
+ * Same as get_rule_expr(), except that if the expr is just a Var, we pass
+ * istoplevel = true not false to get_variable().  This causes whole-row Vars
+ * to get printed with decoration that will prevent expansion of "*".
+ * We need to use this in contexts such as ROW() and VALUES(), where the
+ * parser would expand "foo.*" appearing at top level.  (In principle we'd
+ * use this in get_target_list() too, but that has additional worries about
+ * whether to print AS, so it needs to invoke get_variable() directly anyway.)
+ */
+static void
+get_rule_expr_toplevel(Node *node, deparse_context *context,
+                      bool showimplicit)
+{
+   if (node && IsA(node, Var))
+       (void) get_variable((Var *) node, 0, true, context);
+   else
+       get_rule_expr(node, context, showimplicit);
+}
+
 
 /*
  * get_oper_expr           - Parse back an OpExpr node

diff --git a/src/test/regress/expected/create_view.out b/src/test/regress/expected/create_view.out
index cc93854c423084e1e0a1afdc6d9d67f4c22235e8..6cf0e672c8e3686a4473f6add644a4ca880b72ea 100644 (file)
--- a/src/test/regress/expected/create_view.out
+++ b/src/test/regress/expected/create_view.out
@@ -288,50 +288,67 @@ SELECT relname, relkind, reloptions FROM pg_class
  mysecview4 | v       | {security_barrier=false}
 (4 rows)
 
+-- check display of whole-row variables in some corner cases
+create type nestedcomposite as (x int8_tbl);
+create view tt15v as select row(i)::nestedcomposite from int8_tbl i;
+select * from tt15v;
+                   row                    
+------------------------------------------
+ ("(123,456)")
+ ("(123,4567890123456789)")
+ ("(4567890123456789,123)")
+ ("(4567890123456789,4567890123456789)")
+ ("(4567890123456789,-4567890123456789)")
+(5 rows)
+
+select pg_get_viewdef('tt15v', true);
+                    pg_get_viewdef                    
+------------------------------------------------------
+  SELECT ROW(i.*::int8_tbl)::nestedcomposite AS "row"+
+    FROM int8_tbl i;
+(1 row)
+
+select row(i.*::int8_tbl)::nestedcomposite from int8_tbl i;
+                   row                    
+------------------------------------------
+ ("(123,456)")
+ ("(123,4567890123456789)")
+ ("(4567890123456789,123)")
+ ("(4567890123456789,4567890123456789)")
+ ("(4567890123456789,-4567890123456789)")
+(5 rows)
+
+create view tt17v as select * from int8_tbl i where i in (values(i));
+select * from tt17v;
+        q1        |        q2         
+------------------+-------------------
+              123 |               456
+              123 |  4567890123456789
+ 4567890123456789 |               123
+ 4567890123456789 |  4567890123456789
+ 4567890123456789 | -4567890123456789
+(5 rows)
+
+select pg_get_viewdef('tt17v', true);
+               pg_get_viewdef                
+---------------------------------------------
+  SELECT i.q1, i.q2                         +
+    FROM int8_tbl i                         +
+   WHERE (i.* IN ( VALUES (i.*::int8_tbl)));
+(1 row)
+
+select * from int8_tbl i where i.* in (values(i.*::int8_tbl));
+        q1        |        q2         
+------------------+-------------------
+              123 |               456
+              123 |  4567890123456789
+ 4567890123456789 |               123
+ 4567890123456789 |  4567890123456789
+ 4567890123456789 | -4567890123456789
+(5 rows)
+
+-- clean up all the random objects we made above
+set client_min_messages = warning;
 DROP SCHEMA temp_view_test CASCADE;
-NOTICE:  drop cascades to 22 other objects
-DETAIL:  drop cascades to table temp_view_test.base_table
-drop cascades to view v7_temp
-drop cascades to view v10_temp
-drop cascades to view v11_temp
-drop cascades to view v12_temp
-drop cascades to view v2_temp
-drop cascades to view v4_temp
-drop cascades to view v6_temp
-drop cascades to view v8_temp
-drop cascades to view v9_temp
-drop cascades to table temp_view_test.base_table2
-drop cascades to view v5_temp
-drop cascades to view temp_view_test.v1
-drop cascades to view temp_view_test.v2
-drop cascades to view temp_view_test.v3
-drop cascades to view temp_view_test.v4
-drop cascades to view temp_view_test.v5
-drop cascades to view temp_view_test.v6
-drop cascades to view temp_view_test.v7
-drop cascades to view temp_view_test.v8
-drop cascades to sequence temp_view_test.seq1
-drop cascades to view temp_view_test.v9
 DROP SCHEMA testviewschm2 CASCADE;
-NOTICE:  drop cascades to 20 other objects
-DETAIL:  drop cascades to table t1
-drop cascades to view temporal1
-drop cascades to view temporal2
-drop cascades to view temporal3
-drop cascades to view temporal4
-drop cascades to table t2
-drop cascades to view nontemp1
-drop cascades to view nontemp2
-drop cascades to view nontemp3
-drop cascades to view nontemp4
-drop cascades to table tbl1
-drop cascades to table tbl2
-drop cascades to table tbl3
-drop cascades to table tbl4
-drop cascades to view mytempview
-drop cascades to view pubview
-drop cascades to view mysecview1
-drop cascades to view mysecview2
-drop cascades to view mysecview3
-drop cascades to view mysecview4
 SET search_path to public;

diff --git a/src/test/regress/sql/create_view.sql b/src/test/regress/sql/create_view.sql
index 48d8d22d1b8e4e997f1bd236b75a2b7773a6ad7f..f13c9af2e891304e779691aca59e67080be2549b 100644 (file)
--- a/src/test/regress/sql/create_view.sql
+++ b/src/test/regress/sql/create_view.sql
@@ -224,6 +224,21 @@ SELECT relname, relkind, reloptions FROM pg_class
                      'mysecview3'::regclass, 'mysecview4'::regclass)
        ORDER BY relname;
 
+-- check display of whole-row variables in some corner cases
+
+create type nestedcomposite as (x int8_tbl);
+create view tt15v as select row(i)::nestedcomposite from int8_tbl i;
+select * from tt15v;
+select pg_get_viewdef('tt15v', true);
+select row(i.*::int8_tbl)::nestedcomposite from int8_tbl i;
+
+create view tt17v as select * from int8_tbl i where i in (values(i));
+select * from tt17v;
+select pg_get_viewdef('tt17v', true);
+select * from int8_tbl i where i.* in (values(i.*::int8_tbl));
+
+-- clean up all the random objects we made above
+set client_min_messages = warning;
 DROP SCHEMA temp_view_test CASCADE;
 DROP SCHEMA testviewschm2 CASCADE;