Jake Magner writes:
> I tried without doing an INSERT at all, just running the SELECT queries and
> the result is the same. Nested loop is chosen but is much slower.
FWIW, I just noticed that the comparisons you're using are plain equality
of the arrays. While a GIN array index supports that, it
I tried without doing an INSERT at all, just running the SELECT queries and
the result is the same. Nested loop is chosen but is much slower.
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Jake Magner writes:
> I am trying to insert rows that don't already exist from a temp table into
> another table. I am using a LEFT JOIN on all the columns and checking for
> nulls in the base table to know which rows to insert. The problem is that
> the planner is choosing a nested loop plan whic
I am trying to insert rows that don't already exist from a temp table into
another table. I am using a LEFT JOIN on all the columns and checking for
nulls in the base table to know which rows to insert. The problem is that
the planner is choosing a nested loop plan which is very slow over the much
>
> ...(BTW, I wonder why you are moving only to 9.2 and not something more
>> recent.)
>>
>
> Well, 9.2.15 is what comes bundled with RHEL 7, so I decided to go with
> that to avoid dependency issues. But I could install a more fresh version
> from scratch if that would solve my problem.
>
Genera
The rowcount estimates from 9.2 seem greatly different from the 8.4 plan.
Did you remember to ANALYZE all the tables after migrating? Maybe there
were some table-specific statistics targets that you forgot to transfer
over?
No, I did not. Honestly I though everything would be transfered with a
Johan Fredriksson writes:
> I am just about to upgrade from PostgreSQL 8.4.20 to 9.2.15, but I'v run
> into some huge performance issues.
The rowcount estimates from 9.2 seem greatly different from the 8.4 plan.
Did you remember to ANALYZE all the tables after migrating? Maybe there
were some ta
Hello!
I am just about to upgrade from PostgreSQL 8.4.20 to 9.2.15, but I'v run
into some huge performance issues. Both databases are configured the
same way (shared_buffers = 2GB, temp_buffers = 32MB). I have increased
work_mem on the 9.2 from 4MB to 64MB, but to no avail.
Now, the query on 8.4:
