Sriram Dandapani wrote:
Parent table has a column say column1 which is indexed (parent table and
all child tables are indexed on that column)
Do you mean?
select max(foo) from bar;
In older versions of postgresql that would scan the whole table. In 8.1
and above it doesn't. However, I am guess that since this is a
partitioned table the planner isn't smart enough to just perform the
query on each child and a max on the set that is returned. Thus you are
scanning each table completely.
But that is just a guess.
Joshua D. Drake
When a select max(column1) is done on parent table..takes a very long
time to get back with the result
The same query on a child table gives instantaneous response (the tables
are quite large appx.each child table has about 20-30 million rows)
Constraint exclusion is turned on. The column is not the basis for
partitioning. Postgres 8.1.2
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