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| author | Robert Haas <rhaas@postgresql.org> | 2017-02-14 18:09:47 -0500 |
|---|---|---|
| committer | Robert Haas <rhaas@postgresql.org> | 2017-02-14 18:16:03 -0500 |
| commit | 5e6d8d2bbbcace304450b309e79366c0da4063e4 (patch) | |
| tree | d5068ced430d295491c0b34c39415e8f49fad6da /src/test/regress/sql/select_parallel.sql | |
| parent | 8da9a226369e9ceec7cef1ab7a16cdc0adb4d657 (diff) | |
| download | postgresql-5e6d8d2bbbcace304450b309e79366c0da4063e4.tar.gz postgresql-5e6d8d2bbbcace304450b309e79366c0da4063e4.zip | |
Allow parallel workers to execute subplans.
This doesn't do anything to make Param nodes anything other than
parallel-restricted, so this only helps with uncorrelated subplans,
and it's not necessarily very cheap because each worker will run the
subplan separately (just as a Hash Join will build a separate copy of
the hash table in each participating process), but it's a first step
toward supporting cases that are more likely to help in practice, and
is occasionally useful on its own.
Amit Kapila, reviewed and tested by Rafia Sabih, Dilip Kumar, and
me.
Discussion: http://postgr.es/m/CAA4eK1+e8Z45D2n+rnDMDYsVEb5iW7jqaCH_tvPMYau=1Rru9w@mail.gmail.com
Diffstat (limited to 'src/test/regress/sql/select_parallel.sql')
| -rw-r--r-- | src/test/regress/sql/select_parallel.sql | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/test/regress/sql/select_parallel.sql b/src/test/regress/sql/select_parallel.sql index 8b4090f2ec1..def9939d2e6 100644 --- a/src/test/regress/sql/select_parallel.sql +++ b/src/test/regress/sql/select_parallel.sql @@ -39,6 +39,15 @@ explain (costs off) select sum(parallel_restricted(unique1)) from tenk1 group by(parallel_restricted(unique1)); +-- test parallel plans for queries containing un-correlated subplans. +alter table tenk2 set (parallel_workers = 0); +explain (costs off) + select count(*) from tenk1 where (two, four) not in + (select hundred, thousand from tenk2 where thousand > 100); +select count(*) from tenk1 where (two, four) not in + (select hundred, thousand from tenk2 where thousand > 100); +alter table tenk2 reset (parallel_workers); + set force_parallel_mode=1; explain (costs off) |