\set num_rows 1000000 drop table t1; drop table p cascade; create table t1 (a int, b varchar, c timestamp) partition by range(a); create table t1p1 (b varchar, c timestamp, a int) partition by range(a); alter table t1 attach partition t1p1 for values from (0) to (100); create table t1p1p1(c timestamp, a int, b varchar); alter table t1p1 attach partition t1p1p1 for values from (0) to (50); insert into t1 select abs(random()) * 49, i, now() from generate_series(1, :num_rows) i; explain analyze select t1 from t1; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ Append (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.079..683.430 rows=1000000 loops=1) -> Seq Scan on t1p1p1 (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.077..616.439 rows=1000000 loops=1) Planning time: 0.193 ms Execution time: 717.929 ms (4 rows) explain analyze select t1 from t1; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ Append (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.017..607.063 rows=1000000 loops=1) -> Seq Scan on t1p1p1 (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.016..541.619 rows=1000000 loops=1) Planning time: 0.115 ms Execution time: 640.628 ms (4 rows) explain analyze select t1 from t1; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ Append (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.016..605.972 rows=1000000 loops=1) -> Seq Scan on t1p1p1 (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.016..541.256 rows=1000000 loops=1) Planning time: 0.109 ms Execution time: 639.426 ms (4 rows) explain analyze select t1 from t1; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ Append (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.017..613.866 rows=1000000 loops=1) -> Seq Scan on t1p1p1 (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.017..548.002 rows=1000000 loops=1) Planning time: 0.112 ms Execution time: 647.820 ms (4 rows) explain analyze select t1 from t1; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ Append (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.016..612.391 rows=1000000 loops=1) -> Seq Scan on t1p1p1 (cost=0.00..13565.97 rows=719697 width=32) (actual time=0.016..546.605 rows=1000000 loops=1) Planning time: 0.111 ms Execution time: 646.292 ms (4 rows) create table p (a int, b varchar, c timestamp); create table p_c (b varchar, c timestamp, a int, d int); alter table p_c inherit p; create table p_c_c (c timestamp, a int, b varchar, d int, e int); alter table p_c_c inherit p_c; insert into p_c_c select c, a, b, a, a from t1; explain analyze select p from p; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- Append (cost=0.00..14851.04 rows=749906 width=32) (actual time=0.044..737.725 rows=1000000 loops=1) -> Seq Scan on p (cost=0.00..0.00 rows=1 width=68) (actual time=0.002..0.002 rows=0 loops=1) -> Seq Scan on p_c (cost=0.00..0.00 rows=1 width=32) (actual time=0.000..0.000 rows=0 loops=1) -> Seq Scan on p_c_c (cost=0.00..14851.04 rows=749904 width=32) (actual time=0.042..672.052 rows=1000000 loops=1) Planning time: 0.194 ms Execution time: 772.241 ms (6 rows) explain analyze select p from p; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- Append (cost=0.00..14851.04 rows=749906 width=32) (actual time=0.018..677.591 rows=1000000 loops=1) -> Seq Scan on p (cost=0.00..0.00 rows=1 width=68) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c (cost=0.00..0.00 rows=1 width=32) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c_c (cost=0.00..14851.04 rows=749904 width=32) (actual time=0.016..611.849 rows=1000000 loops=1) Planning time: 0.098 ms Execution time: 711.619 ms (6 rows) explain analyze select p from p; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- Append (cost=0.00..14851.04 rows=749906 width=32) (actual time=0.018..684.336 rows=1000000 loops=1) -> Seq Scan on p (cost=0.00..0.00 rows=1 width=68) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c (cost=0.00..0.00 rows=1 width=32) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c_c (cost=0.00..14851.04 rows=749904 width=32) (actual time=0.015..618.316 rows=1000000 loops=1) Planning time: 0.104 ms Execution time: 718.329 ms (6 rows) explain analyze select p from p; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- Append (cost=0.00..14851.04 rows=749906 width=32) (actual time=0.018..677.647 rows=1000000 loops=1) -> Seq Scan on p (cost=0.00..0.00 rows=1 width=68) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c (cost=0.00..0.00 rows=1 width=32) (actual time=0.000..0.000 rows=0 loops=1) -> Seq Scan on p_c_c (cost=0.00..14851.04 rows=749904 width=32) (actual time=0.016..611.973 rows=1000000 loops=1) Planning time: 0.098 ms Execution time: 711.535 ms (6 rows) explain analyze select p from p; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- Append (cost=0.00..14851.04 rows=749906 width=32) (actual time=0.018..675.063 rows=1000000 loops=1) -> Seq Scan on p (cost=0.00..0.00 rows=1 width=68) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c (cost=0.00..0.00 rows=1 width=32) (actual time=0.001..0.001 rows=0 loops=1) -> Seq Scan on p_c_c (cost=0.00..14851.04 rows=749904 width=32) (actual time=0.016..609.450 rows=1000000 loops=1) Planning time: 0.098 ms Execution time: 708.892 ms (6 rows)