Move materialized views' is-populated status into their pg_class entries.

Previously this state was represented by whether the view's disk file had
zero or nonzero size, which is problematic for numerous reasons, since it's
breaking a fundamental assumption about heap storage.  This was done to
allow unlogged matviews to revert to unpopulated status after a crash
despite our lack of any ability to update catalog entries post-crash.
However, this poses enough risk of future problems that it seems better to
not support unlogged matviews until we can find another way.  Accordingly,
revert that choice as well as a number of existing kluges forced by it
in favor of creating a pg_class.relispopulated flag column.

3 files changed, 13 insertions, 13 deletions

diff --git a/src/test/regress/expected/matview.out b/src/test/regress/expected/matview.out
index 06bb2551a83..a98de4f58d3 100644
--- a/src/test/regress/expected/matview.out
+++ b/src/test/regress/expected/matview.out
@@ -26,9 +26,9 @@ EXPLAIN (costs off)
 (2 rows)
 
 CREATE MATERIALIZED VIEW tm AS SELECT type, sum(amt) AS totamt FROM t GROUP BY type WITH NO DATA;
-SELECT pg_relation_is_scannable('tm'::regclass);
- pg_relation_is_scannable 
---------------------------
+SELECT relispopulated FROM pg_class WHERE oid = 'tm'::regclass;
+ relispopulated 
+----------------
  f
 (1 row)
 
@@ -36,9 +36,9 @@ SELECT * FROM tm;
 ERROR:  materialized view "tm" has not been populated
 HINT:  Use the REFRESH MATERIALIZED VIEW command.
 REFRESH MATERIALIZED VIEW tm;
-SELECT pg_relation_is_scannable('tm'::regclass);
- pg_relation_is_scannable 
---------------------------
+SELECT relispopulated FROM pg_class WHERE oid = 'tm'::regclass;
+ relispopulated 
+----------------
  t
 (1 row)
 
@@ -354,9 +354,9 @@ UNION ALL
            FROM v_test2;
 
 CREATE MATERIALIZED VIEW mv_test3 AS SELECT * FROM mv_test2 WHERE moo = 12345;
-SELECT pg_relation_is_scannable('mv_test3'::regclass);
- pg_relation_is_scannable 
---------------------------
+SELECT relispopulated FROM pg_class WHERE oid = 'mv_test3'::regclass;
+ relispopulated 
+----------------
  t
 (1 row)
 
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index a4ecfd2aeac..dc3c8a83812 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1347,7 +1347,7 @@ SELECT viewname, definition FROM pg_views WHERE schemaname <> 'information_schem
                                  |     pg_get_userbyid(c.relowner) AS matviewowner,                                                                                                                                                               +
                                  |     t.spcname AS tablespace,                                                                                                                                                                                   +
                                  |     c.relhasindex AS hasindexes,                                                                                                                                                                               +
-                                 |     pg_relation_is_scannable(c.oid) AS isscannable,                                                                                                                                                            +
+                                 |     c.relispopulated AS ispopulated,                                                                                                                                                                           +
                                  |     pg_get_viewdef(c.oid) AS definition                                                                                                                                                                        +
                                  |    FROM ((pg_class c                                                                                                                                                                                           +
                                  |    LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace)))                                                                                                                                                     +
diff --git a/src/test/regress/sql/matview.sql b/src/test/regress/sql/matview.sql
index 09a7378133c..975f8dd5750 100644
--- a/src/test/regress/sql/matview.sql
+++ b/src/test/regress/sql/matview.sql
@@ -15,10 +15,10 @@ SELECT * FROM tv ORDER BY type;
 EXPLAIN (costs off)
   CREATE MATERIALIZED VIEW tm AS SELECT type, sum(amt) AS totamt FROM t GROUP BY type WITH NO DATA;
 CREATE MATERIALIZED VIEW tm AS SELECT type, sum(amt) AS totamt FROM t GROUP BY type WITH NO DATA;
-SELECT pg_relation_is_scannable('tm'::regclass);
+SELECT relispopulated FROM pg_class WHERE oid = 'tm'::regclass;
 SELECT * FROM tm;
 REFRESH MATERIALIZED VIEW tm;
-SELECT pg_relation_is_scannable('tm'::regclass);
+SELECT relispopulated FROM pg_class WHERE oid = 'tm'::regclass;
 CREATE UNIQUE INDEX tm_type ON tm (type);
 SELECT * FROM tm;
 
@@ -109,7 +109,7 @@ CREATE VIEW v_test2 AS SELECT moo, 2*moo FROM v_test1 UNION ALL SELECT moo, 3*mo
 CREATE MATERIALIZED VIEW mv_test2 AS SELECT moo, 2*moo FROM v_test2 UNION ALL SELECT moo, 3*moo FROM v_test2;
 \d+ mv_test2
 CREATE MATERIALIZED VIEW mv_test3 AS SELECT * FROM mv_test2 WHERE moo = 12345;
-SELECT pg_relation_is_scannable('mv_test3'::regclass);
+SELECT relispopulated FROM pg_class WHERE oid = 'mv_test3'::regclass;
 
 DROP VIEW v_test1 CASCADE;