15 questions
6
votes
1
answer
2k
views
Parallel queries on CTE for writing operations in PostgreSQL
From PostgreSQL 9.6 Release Notes:
Only strictly read-only queries where the driving table is accessed via a sequential scan can be parallelized.
My question is: If a CTE (WITH clause) contains only ...
- 1,719
1
vote
1
answer
455
views
Query stops parallelizing when adding LIMIT or ROW_NUMBER
I have 20 tables with identical structure, and I need to aggregate the results.
I'm using UNION ALL to collect the results, in the following structure:
SELECT something, SUM(total) AS overall_total
...
- 668k
2
votes
1
answer
3k
views
Materialized view refresh in parallel
Created materialized view in parallel by setting max_parallel_workers_per_gather to 4. I could see parallel sessions kicking off and creating the mview much faster than serial execution (10mins - ...
- 668k
0
votes
1
answer
2k
views
Is it possible to execute parallel query in Postgres which queries partitioned table by using union all?
Hello I'm playing around with postgres as a search engine by using GIN indexes with trigram module and partitioned table and I'm trying to parallelize the query but no matter what I set the query is ...
- 44.9k
3
votes
2
answers
2k
views
To what degree does PostgreSQL support parallel DDL?
Looking here, it is clear that Oracle supports execution of DDL commands in parallel with scenarios clearly listed. I was wondering whether Postgres does indeed offer such functionality? I can find a ...
CommunityBot
- 1
0
votes
1
answer
231
views
PostgreSQL parallel queries using SPI possible?
I am using PostgreSQL's Server Programming Interface (SPI) to build my postgres extension and execute my query. Please see this detailed example, or the following simple code sample:
int ret = ...
- 44.9k
0
votes
0
answers
2k
views
Postgres does not apply parallel query
I am using "PostgreSQL 11.4, compiled by Visual C++ build 1914, 64-bit"
I want to run parallel query for testing purpose, below is my pg_settings parameter values:
"checkpoint_completion_target" ...
CommunityBot
- 1
5
votes
1
answer
3k
views
Does PostgreSQL query partitions in parallel?
Postgres now has parallel queries. Are parallel queries used when the table is partitioned, the query is on the master table, and more than one partitions (child tables) are involved.
For example, I ...
- 668k