-- -- MULTI_JOIN_PRUNING -- -- Check that join-pruning works for joins between two large relations. For now -- we only check for join-pruning between locally partitioned relations. In the -- future we want to check for pruning between re-partitioned relations as well. SET citus.explain_distributed_queries TO off; SET client_min_messages TO DEBUG2; -- Change configuration to treat all tables as large SET citus.large_table_shard_count TO 2; SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem, orders WHERE l_orderkey = o_orderkey; DEBUG: join prunable for intervals [1,1509] and [8997,14946] DEBUG: join prunable for intervals [1509,2951] and [8997,14946] DEBUG: join prunable for intervals [2951,4455] and [8997,14946] DEBUG: join prunable for intervals [4480,5986] and [8997,14946] DEBUG: join prunable for intervals [8997,10560] and [1,5986] DEBUG: join prunable for intervals [10560,12036] and [1,5986] DEBUG: join prunable for intervals [12036,13473] and [1,5986] DEBUG: join prunable for intervals [13473,14947] and [1,5986] sum | avg -------+-------------------- 36086 | 3.0076679446574429 (1 row) SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem, orders WHERE l_orderkey = o_orderkey AND l_orderkey > 9030; DEBUG: join prunable for intervals [8997,10560] and [1,5986] DEBUG: join prunable for intervals [10560,12036] and [1,5986] DEBUG: join prunable for intervals [12036,13473] and [1,5986] DEBUG: join prunable for intervals [13473,14947] and [1,5986] sum | avg -------+-------------------- 17996 | 3.0194630872483221 (1 row) -- Shards for the lineitem table have been pruned away. Check that join pruning -- works as expected in this case. SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem, orders WHERE l_orderkey = o_orderkey AND l_orderkey > 20000; sum | avg -----+----- | (1 row) -- Partition pruning left three shards for the lineitem and one shard for the -- orders table. These shard sets don't overlap, so join pruning should prune -- out all the shards, and leave us with an empty task list. SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem, orders WHERE l_orderkey = o_orderkey AND l_orderkey > 6000 AND o_orderkey < 6000; DEBUG: join prunable for intervals [8997,10560] and [1,5986] DEBUG: join prunable for intervals [10560,12036] and [1,5986] DEBUG: join prunable for intervals [12036,13473] and [1,5986] DEBUG: join prunable for intervals [13473,14947] and [1,5986] sum | avg -----+----- | (1 row) -- Make sure that we can handle filters without a column SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem, orders WHERE l_orderkey = o_orderkey AND false; sum | avg -----+----- | (1 row) SELECT sum(l_linenumber), avg(l_linenumber) FROM lineitem INNER JOIN orders ON (l_orderkey = o_orderkey) WHERE false; sum | avg -----+----- | (1 row) -- These tests check that we can do join pruning for tables partitioned over -- different type of columns including varchar, array types, composite types -- etc. This is in response to a bug we had where we were not able to resolve -- correct operator types for some kind of column types. EXPLAIN SELECT count(*) FROM array_partitioned_table table1, array_partitioned_table table2 WHERE table1.array_column = table2.array_column; DEBUG: join prunable for intervals [{},{AZZXSP27F21T6,AZZXSP27F21T6}] and [{BA1000U2AMO4ZGX,BZZXSP27F21T6},{CA1000U2AMO4ZGX,CZZXSP27F21T6}] DEBUG: join prunable for intervals [{BA1000U2AMO4ZGX,BZZXSP27F21T6},{CA1000U2AMO4ZGX,CZZXSP27F21T6}] and [{},{AZZXSP27F21T6,AZZXSP27F21T6}] QUERY PLAN ----------------------------------------------------------------------- Aggregate (cost=0.00..0.00 rows=0 width=0) -> Custom Scan (Citus Real-Time) (cost=0.00..0.00 rows=0 width=0) explain statements for distributed queries are not enabled (3 rows) EXPLAIN SELECT count(*) FROM composite_partitioned_table table1, composite_partitioned_table table2 WHERE table1.composite_column = table2.composite_column; DEBUG: join prunable for intervals [(a,3,b),(b,4,c)] and [(c,5,d),(d,6,e)] DEBUG: join prunable for intervals [(c,5,d),(d,6,e)] and [(a,3,b),(b,4,c)] QUERY PLAN ----------------------------------------------------------------------- Aggregate (cost=0.00..0.00 rows=0 width=0) -> Custom Scan (Citus Real-Time) (cost=0.00..0.00 rows=0 width=0) explain statements for distributed queries are not enabled (3 rows) -- Test that large table joins on partition varchar columns work EXPLAIN SELECT count(*) FROM varchar_partitioned_table table1, varchar_partitioned_table table2 WHERE table1.varchar_column = table2.varchar_column; DEBUG: join prunable for intervals [AA1000U2AMO4ZGX,AZZXSP27F21T6] and [BA1000U2AMO4ZGX,BZZXSP27F21T6] DEBUG: join prunable for intervals [BA1000U2AMO4ZGX,BZZXSP27F21T6] and [AA1000U2AMO4ZGX,AZZXSP27F21T6] QUERY PLAN ----------------------------------------------------------------------- Aggregate (cost=0.00..0.00 rows=0 width=0) -> Custom Scan (Citus Real-Time) (cost=0.00..0.00 rows=0 width=0) explain statements for distributed queries are not enabled (3 rows)