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Hi all!
I have a little problem, when using a temp table
....
explain UPDATE cim SET os_cim_id=-1 FROM
T_CNY WHERE cim.cim_id=T_CNY.cim_id;
NOTICE: QUERY PLAN: Hash Join (cost=26986.59..44340.35
rows=243969 width=129)
-> Seq Scan on t_cny (cost=0.00..3635.69 rows=243969 width=4) -> Hash (cost=5961.65..5961.65 rows=254965 width=125) -> Seq Scan on cim (cost=0.00..5961.65 rows=254965 width=125) In this case t_cny is a temp table and update runs
very very slow ...
After I copied t_cny a real table named tcny
:
select * into tcny from t_cny;
explain UPDATE cim SET os_cim_id=-1 FROM TCNY WHERE
cim.cim_id=TCNY.cim_id;
NOTICE: QUERY PLAN:
Nested Loop (cost=0.00..3321.34 rows=1000
width=129)
-> Seq Scan on tcny (cost=0.00..20.00 rows=1000 width=4) -> Index Scan using pk_cim on cim (cost=0.00..3.29 rows=1 width=125) Postgres's query optimizer does not determine a temp table field
information ???
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