Use one of not-null unique keys to identify rows when the target table doesn't

have a primary key. Some of users want to use not-null unique keys rather than
primary keys because postgres doesn't support REINDEX PRIMARY KEY CONCURRENTLY.

- Support 9.1dev.
- Improve Makefile to use PGXS automatically.

lib/Makefile

@@ -9,13 +9,21 @@ MODULE_big = pg_reorg
 DATA_built = pg_reorg.sql
 DATA = uninstall_pg_reorg.sql
 
+ifndef USE_PGXS
+top_builddir = ../../..
+makefile_global = $(top_builddir)/src/Makefile.global
+ifeq "$(wildcard $(makefile_global))" ""
+USE_PGXS = 1	# use pgxs if not in contrib directory
+endif
+endif
+
 ifdef USE_PGXS
-PGXS := $(shell pg_config --pgxs)
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 else
-subdir = contrib/pg_reorg
-top_builddir = ../../..
-include $(top_builddir)/src/Makefile.global
+subdir = contrib/$(MODULE_big)
+include $(makefile_global)
 include $(top_srcdir)/contrib/contrib-global.mk
 endif
 

lib/pg_reorg.sql.in

@@ -106,6 +106,20 @@ $$
 $$
 LANGUAGE sql STABLE STRICT;
 
+-- includes not only PRIMARY KEYS but also UNIQUE NOT NULL keys
+CREATE VIEW reorg.primary_keys AS
+  SELECT indrelid, (reorg.array_accum(indexrelid))[1] AS indexrelid
+    FROM (SELECT indrelid, indexrelid FROM pg_index
+   WHERE indisunique
+     AND 0 <> ALL(indkey)
+     AND NOT EXISTS(
+           SELECT 1 FROM pg_attribute
+            WHERE attrelid = indrelid
+              AND attnum = ANY(indkey)
+              AND NOT attnotnull)
+   ORDER BY indrelid, indisprimary DESC, indnatts, indkey) tmp
+   GROUP BY indrelid;
+
 CREATE VIEW reorg.tables AS
   SELECT R.oid::regclass AS relname,
          R.oid AS relid,
@@ -127,10 +141,13 @@ CREATE VIEW reorg.tables AS
          'DELETE FROM reorg.log_' || R.oid || ' WHERE id <= $1' AS sql_pop
     FROM pg_class R
          LEFT JOIN pg_class T ON R.reltoastrelid = T.oid
-         LEFT JOIN (SELECT * FROM pg_index WHERE indisprimary) PK
+         LEFT JOIN reorg.primary_keys PK
                 ON R.oid = PK.indrelid
          LEFT JOIN (SELECT CKI.* FROM pg_index CKI, pg_class CKT
-                    WHERE CKI.indexrelid = CKT.oid AND CKI.indisclustered AND CKT.relam = 403) CK
+                     WHERE CKI.indisvalid
+                       AND CKI.indexrelid = CKT.oid
+                       AND CKI.indisclustered
+                       AND CKT.relam = 403) CK
                 ON R.oid = CK.indrelid
          LEFT JOIN pg_namespace N ON N.oid = R.relnamespace
          LEFT JOIN pg_tablespace S ON S.oid = R.reltablespace

lib/pgut/pgut-be.h

@@ -151,6 +151,12 @@ extern void tuplestore_putvalues(Tuplestorestate *state, TupleDesc tdesc,
 
 #endif
 
+#if PG_VERSION_NUM < 90100
+
+#define ATExecChangeOwner(relationOid, newOwnerId, recursing, lockmode) \
+	ATExecChangeOwner((relationOid), (newOwnerId), (recursing))
+#endif
+
 #if PG_VERSION_NUM < 80300
 #define RelationSetNewRelfilenode(rel, xid) \
 	setNewRelfilenode((rel))

lib/reorg.c

@@ -766,7 +766,7 @@ reorg_swap(PG_FUNCTION_ARGS)
 	/* change owner of new relation to original owner */
 	if (owner1 != owner2)
 	{
-		ATExecChangeOwner(oid2, owner1, true);
+		ATExecChangeOwner(oid2, owner1, true, AccessExclusiveLock);
 		CommandCounterIncrement();
 	}