Adjust code to PG14 reltuples changes

PG14 changes the initial value of pg_class.reltuples to -1 to allow
differentiating between an empty relation and a relation where
ANALYZE has not yet run.

https://github.com/postgres/postgres/commit/3d351d916b

.github/workflows/postgres_dev.yaml

@@ -10,7 +10,7 @@ jobs:
       PG_INSTALL_DIR: postgresql
       MAKE_JOBS: 2
       # postgres version to build against this can either be commit hash, branch or tag
-      PG_COMMIT: 5028981923
+      PG_COMMIT: 3d351d916b
       CLANG: clang-9
       LLVM_CONFIG: llvm-config-9
       CC: gcc

sql/size_utils.sql

@@ -376,7 +376,7 @@ DECLARE
 	row_count_parent BIGINT;
 	row_count        BIGINT;
 BEGIN
-	SELECT relname, nspname, c.reltuples::bigint
+	SELECT relname, nspname, CASE WHEN c.reltuples > 0 THEN c.reltuples::bigint ELSE 0 END
 	INTO table_name, schema_name, row_count_parent
 	FROM pg_class c
 	INNER JOIN pg_namespace n ON (n.OID = c.relnamespace)
@@ -394,7 +394,7 @@ BEGIN
 		FROM pg_inherits i
 		JOIN inherited_id b ON i.inhparent = b.oid
 	)
-	SELECT sum(child.reltuples)::bigint
+	SELECT sum(CASE WHEN child.reltuples > 0 THEN child.reltuples ELSE 0 END)::bigint
 	INTO row_count
 	FROM inherited_id i
 	JOIN pg_class child ON i.oid = child.oid

tsl/src/chunk_api.c

@@ -512,6 +512,7 @@ chunk_get_single_stats_tuple(Chunk *chunk, TupleDesc tupdesc)
 	Form_pg_class pgcform;
 	Datum values[_Anum_chunk_relstats_max];
 	bool nulls[_Anum_chunk_relstats_max] = { false };
+	float reltuples = 0;
 
 	ctup = SearchSysCache1(RELOID, ObjectIdGetDatum(chunk->table_id));
 
@@ -528,8 +529,8 @@ chunk_get_single_stats_tuple(Chunk *chunk, TupleDesc tupdesc)
 		Int32GetDatum(chunk->fd.hypertable_id);
 	values[AttrNumberGetAttrOffset(Anum_chunk_relstats_num_pages)] =
 		Int32GetDatum(pgcform->relpages);
-	values[AttrNumberGetAttrOffset(Anum_chunk_relstats_num_tuples)] =
-		Float4GetDatum(pgcform->reltuples);
+	reltuples = Float4GetDatum(pgcform->reltuples);
+	values[AttrNumberGetAttrOffset(Anum_chunk_relstats_num_tuples)] = reltuples > 0 ? reltuples : 0;
 	values[AttrNumberGetAttrOffset(Anum_chunk_relstats_num_allvisible)] =
 		Int32GetDatum(pgcform->relallvisible);
 

tsl/src/fdw/relinfo.c

@@ -341,7 +341,7 @@ estimate_tuples_and_pages(PlannerInfo *root, RelOptInfo *rel)
 	Hyperspace *hyperspace;
 	RelEstimates *estimates;
 
-	Assert(rel->tuples == 0);
+	Assert(rel->tuples <= 0);
 	Assert(rel->pages == 0);
 
 	/* In some cases (e.g., UPDATE stmt) top_parent_relids is not set so the best
@@ -366,7 +366,7 @@ estimate_tuples_and_pages(PlannerInfo *root, RelOptInfo *rel)
 	/* Let's first try figuring out number of tuples/pages using stats from previous chunks,
 	otherwise make an estimation based on shared buffers size */
 	estimates = estimate_tuples_and_pages_using_prev_chunks(root, hyperspace, chunk);
-	if (estimates->tuples == 0 || estimates->pages == 0)
+	if (estimates->tuples <= 0 || estimates->pages == 0)
 		estimates = estimate_tuples_and_pages_using_shared_buffers(root, ht, rel->reltarget->width);
 
 	chunk_fillfactor = estimate_chunk_fillfactor(chunk, hyperspace);
@@ -478,9 +478,10 @@ fdw_relinfo_create(PlannerInfo *root, RelOptInfo *rel, Oid server_oid, Oid local
 	/*
 	 * If the foreign table has never been ANALYZEd, it will have relpages
 	 * and reltuples equal to zero, which most likely has nothing to do
-	 * with reality. The best we can do is estimate number of tuples/pages.
+	 * with reality. Starting with PG14 it will have reltuples < 0, meaning
+	 * "unknown". The best we can do is estimate number of tuples/pages.
 	 */
-	if (rel->pages == 0 && rel->tuples == 0 && type == TS_FDW_RELINFO_FOREIGN_TABLE)
+	if (rel->pages == 0 && rel->tuples <= 0 && type == TS_FDW_RELINFO_FOREIGN_TABLE)
 		estimate_tuples_and_pages(root, rel);
 
 	/* Estimate rel size as best we can with local statistics. There are

tsl/test/expected/chunk_api.out

@@ -162,7 +162,8 @@ SELECT * FROM _timescaledb_internal.get_chunk_colstats('chunkapi');
 ----------+---------------+---------+----------+-------+-------------+----------+---------------+----------------+--------------+--------------+--------------+--------------+--------------+---------------------+-------------+-------------+-------------+-------------+-------------
 (0 rows)
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class WHERE relname IN
+-- reltuples is -1 on PG14 when no VACUUM/ANALYZE has run yet
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class WHERE relname IN
 (SELECT (_timescaledb_internal.show_chunk(show_chunks)).table_name
  FROM show_chunks('chunkapi'))
 ORDER BY relname;

tsl/test/expected/compression.out

@@ -1286,7 +1286,8 @@ FROM _timescaledb_catalog.hypertable ht, _timescaledb_catalog.chunk ch
        , _timescaledb_catalog.chunk compch 
   WHERE ht.table_name = 'stattest' AND ch.hypertable_id = ht.id
         AND compch.id = ch.compressed_chunk_id AND ch.compressed_chunk_id > 0  \gset
-SELECT relpages, reltuples FROM pg_class WHERE relname = :'STAT_COMP_CHUNK_NAME';
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE was run
+SELECT relpages, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples FROM pg_class WHERE relname = :'STAT_COMP_CHUNK_NAME';
  relpages | reltuples 
 ----------+-----------
         0 |         0
@@ -1401,7 +1402,8 @@ WHERE ch1.hypertable_id = ht.id and ht.table_name like 'stattest2'
  _timescaledb_internal._hyper_29_58_chunk
 (1 row)
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )
@@ -1422,7 +1424,8 @@ SET reltuples = 0, relpages = 0
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id 
         AND ch.compressed_chunk_id > 0 );
 \c :TEST_DBNAME :ROLE_DEFAULT_PERM_USER
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )
@@ -1439,7 +1442,8 @@ FROM _timescaledb_catalog.hypertable ht, _timescaledb_catalog.hypertable compht
 WHERE ht.table_name = 'stattest2' AND ht.compressed_hypertable_id = compht.id \gset
 --analyze the compressed table, will update stats for the raw table.
 ANALYZE :STAT_COMP_TABLE;
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )

tsl/test/expected/dist_hypertable-12.out

@@ -232,7 +232,8 @@ INSERT INTO disttable VALUES
 -- Test distributed ANALYZE.
 --
 -- First show no statistics
-SELECT relname, relkind, reltuples, relpages
+-- reltuples is initially -1 before any VACUUM/ANALYZE has been run on PG14
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;
   relname  | relkind | reltuples | relpages 
@@ -240,7 +241,7 @@ WHERE oid = 'disttable'::regclass;
  disttable | r       |         0 |        0
 (1 row)
 
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class cl, (SELECT show_chunks AS chunk FROM show_chunks('disttable')) ch
 WHERE cl.oid = ch.chunk::regclass;
         relname        | relkind | reltuples | relpages 
@@ -255,7 +256,7 @@ WHERE cl.oid = ch.chunk::regclass;
 
 ANALYZE disttable;
 -- Show updated statistics
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;
   relname  | relkind | reltuples | relpages 

tsl/test/expected/dist_hypertable-13.out

@@ -232,7 +232,8 @@ INSERT INTO disttable VALUES
 -- Test distributed ANALYZE.
 --
 -- First show no statistics
-SELECT relname, relkind, reltuples, relpages
+-- reltuples is initially -1 before any VACUUM/ANALYZE has been run on PG14
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;
   relname  | relkind | reltuples | relpages 
@@ -240,7 +241,7 @@ WHERE oid = 'disttable'::regclass;
  disttable | r       |         0 |        0
 (1 row)
 
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class cl, (SELECT show_chunks AS chunk FROM show_chunks('disttable')) ch
 WHERE cl.oid = ch.chunk::regclass;
         relname        | relkind | reltuples | relpages 
@@ -255,7 +256,7 @@ WHERE cl.oid = ch.chunk::regclass;
 
 ANALYZE disttable;
 -- Show updated statistics
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;
   relname  | relkind | reltuples | relpages 

tsl/test/sql/chunk_api.sql

@@ -85,7 +85,8 @@ ORDER BY chunk_id;
 SELECT * FROM _timescaledb_internal.get_chunk_relstats('chunkapi');
 SELECT * FROM _timescaledb_internal.get_chunk_colstats('chunkapi');
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class WHERE relname IN
+-- reltuples is -1 on PG14 when no VACUUM/ANALYZE has run yet
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class WHERE relname IN
 (SELECT (_timescaledb_internal.show_chunk(show_chunks)).table_name
  FROM show_chunks('chunkapi'))
 ORDER BY relname;

tsl/test/sql/compression.sql

@@ -541,7 +541,8 @@ FROM _timescaledb_catalog.hypertable ht, _timescaledb_catalog.chunk ch
   WHERE ht.table_name = 'stattest' AND ch.hypertable_id = ht.id
         AND compch.id = ch.compressed_chunk_id AND ch.compressed_chunk_id > 0  \gset
 
-SELECT relpages, reltuples FROM pg_class WHERE relname = :'STAT_COMP_CHUNK_NAME';
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE was run
+SELECT relpages, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples FROM pg_class WHERE relname = :'STAT_COMP_CHUNK_NAME';
 
 -- Now verify stats are not changed when we analyze the hypertable
 ANALYZE stattest;
@@ -584,7 +585,8 @@ FROM _timescaledb_catalog.chunk ch1, _timescaledb_catalog.hypertable ht
 WHERE ch1.hypertable_id = ht.id and ht.table_name like 'stattest2'
  ORDER BY ch1.id limit 1;
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )
@@ -602,7 +604,8 @@ SET reltuples = 0, relpages = 0
         AND ch.compressed_chunk_id > 0 );
 \c :TEST_DBNAME :ROLE_DEFAULT_PERM_USER
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )
@@ -616,7 +619,8 @@ WHERE ht.table_name = 'stattest2' AND ht.compressed_hypertable_id = compht.id \g
 --analyze the compressed table, will update stats for the raw table.
 ANALYZE :STAT_COMP_TABLE;
 
-SELECT relname, reltuples, relpages, relallvisible FROM pg_class
+-- reltuples is initially -1 on PG14 before VACUUM/ANALYZE has been run
+SELECT relname, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages, relallvisible FROM pg_class
  WHERE relname in ( SELECT ch.table_name FROM 
                    _timescaledb_catalog.chunk ch, _timescaledb_catalog.hypertable ht
   WHERE ht.table_name = 'stattest2' AND ch.hypertable_id = ht.id )

tsl/test/sql/dist_hypertable.sql.in

@@ -173,18 +173,19 @@ INSERT INTO disttable VALUES
 --
 
 -- First show no statistics
-SELECT relname, relkind, reltuples, relpages
+-- reltuples is initially -1 before any VACUUM/ANALYZE has been run on PG14
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;
 
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class cl, (SELECT show_chunks AS chunk FROM show_chunks('disttable')) ch
 WHERE cl.oid = ch.chunk::regclass;
 
 ANALYZE disttable;
 
 -- Show updated statistics
-SELECT relname, relkind, reltuples, relpages
+SELECT relname, relkind, CASE WHEN reltuples > 0 THEN reltuples ELSE 0 END AS reltuples, relpages
 FROM pg_class
 WHERE oid = 'disttable'::regclass;