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От Илья Конюхов
Тема ...
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Msg-id E1EU3wZ-000Fgr-00.ilyakon-mail-ru@f21.mail.ru
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Список pgsql-sql
> For example, consider the queres:
> 
> SELECT * FROM table1 WHERE field1=1 AND field2=1;
> 
> SELECT * FROM table1 WHERE field2=1 AND field1=1;
> 
> 
> These two queries are logically equivalent. But in all cases the planner generates a query plan that performs
field1=1condition, and then field2=1 condition, as there is a index on field1.
 
> 
> Is it possible to instruct the PostgreSQL query planner to perform field2=1 condition first, and then field1=1
condition?
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
> 

EXPLAIN [ ANALYZE ] [ VERBOSE ] statement
This command displays the execution plan that the PostgreSQL planner generates for the supplied statement.

This command displays plan ONLY! But I want to instruct the PostgreSQL query planner to perform field2=1 condition
first,and then field1=1 condition.
 


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