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| author | Robert Haas <rhaas@postgresql.org> | 2017-10-27 22:22:39 +0200 |
|---|---|---|
| committer | Robert Haas <rhaas@postgresql.org> | 2017-10-27 22:22:39 +0200 |
| commit | 682ce911f8f30de39b13cf211fc8ceb8c6cbc01b (patch) | |
| tree | 36caf44ee3d2da6af8fef9b9366ff4432e7ea91b /src/test | |
| parent | 6784d7a1dc69d53b7f41eebf62bf7ffd63885294 (diff) | |
Allow parallel query for prepared statements with generic plans.
This was always intended to work, but due to an oversight in
max_parallel_hazard_walker, it didn't. In testing, we missed the
fact that it was only working for custom plans, where the parameter
value has been substituted for the parameter itself early enough
that everything worked. In a generic plan, the Param node survives
and must be treated as parallel-safe. SerializeParamList provides
for the transmission of parameter values to workers.
Amit Kapila with help from Kuntal Ghosh. Some changes by me.
Discussion: http://postgr.es/m/CAA4eK1+_BuZrmVCeua5Eqnm4Co9DAXdM5HPAOE2J19ePbR912Q@mail.gmail.com
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/select_parallel.out | 20 | ||||
| -rw-r--r-- | src/test/regress/sql/select_parallel.sql | 6 |
2 files changed, 26 insertions, 0 deletions
diff --git a/src/test/regress/expected/select_parallel.out b/src/test/regress/expected/select_parallel.out index 2ae600f1bbb..3c63ad1de86 100644 --- a/src/test/regress/expected/select_parallel.out +++ b/src/test/regress/expected/select_parallel.out @@ -101,6 +101,26 @@ explain (costs off) -> Parallel Index Only Scan using tenk1_unique1 on tenk1 (5 rows) +-- test prepared statement +prepare tenk1_count(integer) As select count((unique1)) from tenk1 where hundred > $1; +explain (costs off) execute tenk1_count(1); + QUERY PLAN +---------------------------------------------- + Finalize Aggregate + -> Gather + Workers Planned: 4 + -> Partial Aggregate + -> Parallel Seq Scan on tenk1 + Filter: (hundred > 1) +(6 rows) + +execute tenk1_count(1); + count +------- + 9800 +(1 row) + +deallocate tenk1_count; -- test parallel plans for queries containing un-correlated subplans. alter table tenk2 set (parallel_workers = 0); explain (costs off) diff --git a/src/test/regress/sql/select_parallel.sql b/src/test/regress/sql/select_parallel.sql index 89fe80a35c2..720495c8117 100644 --- a/src/test/regress/sql/select_parallel.sql +++ b/src/test/regress/sql/select_parallel.sql @@ -39,6 +39,12 @@ explain (costs off) select sum(parallel_restricted(unique1)) from tenk1 group by(parallel_restricted(unique1)); +-- test prepared statement +prepare tenk1_count(integer) As select count((unique1)) from tenk1 where hundred > $1; +explain (costs off) execute tenk1_count(1); +execute tenk1_count(1); +deallocate tenk1_count; + -- test parallel plans for queries containing un-correlated subplans. alter table tenk2 set (parallel_workers = 0); explain (costs off) |