Explain plan for 2 column index - Mailing list pgsql-performance

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Subject Explain plan for 2 column index
Date
Msg-id 0A5B2E3C3A64CA4AB14F76DBCA76DDA44EF9B4@seifur.hnit.is
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Responses Re: Explain plan for 2 column index
List pgsql-performance
I have 2 columns index.
The question is if optimizer can use both columns of an index or not,
i.e. the plan should read like this:

    Index Cond:
    ((name)::text = 'name1'::text)
    AND ((date_from)::timestamp with time zone=
('now'::text)::timestamp(6) with time zone)

Whilst I am getting index scan on first column and filter on the other:

 Index Scan using testtab_name_date_from on testtab  (cost=0.00..2.01 rows=1
width=18)
   Index Cond: ((name)::text = 'name1'::text)
   Filter: ((date_from)::timestamp with time zone =
('now'::text)::timestamp(6)with time zone)

Could the problem be timestamp column or timestamp with time zones?

Thank you,
Laimis
-------------------------------------------
Bellow are details of the test:


Create table testtab (name varchar(10), date_from timestamp);


create index testtab_name_date_from on testtab(name, date_from) ;


populated table with pseudo random data (10000), analyzed and tuned optimizer
to favour indexes instead of sequential scans.


Pg config:

random_page_cost = 0
cpu_index_tuple_cost = 0.0
enable_seqscan = false
cpu_tuple_cost = 1

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