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Re: Suboptimal query plan fixed by replacing OR with UNION

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I note you've decided to rewrite this query as a union 

> SELECT * FROM account
>   WHERE user_id in 
>     (SELECT user_id FROM account 
>       WHERE id = ANY('{00000000-02f6-379d-c000-000000026810,00000000-0320-b467-c000-000000026810,00000000-000d-cefb-c000-000000026810}'))
>   OR
>     id = ANY('{00000000-02f6-379d-c000-000000026810,00000000-0320-b467-c000-000000026810,00000000-000d-cefb-c000-000000026810}');

I notice both arrays (used with = ANY) have the exact same content,

if this is always true you can use a CTE here for the ID=ANY(...)
query and reference the CTE on both sides of the union.

WITH i as (
 SELECT * FROM account WHERE id = ANY('{00000000-02f6-379d-c000-000000026810,00000000-0320-b467-c000-000000026810,00000000-000d-cefb-c000-000000026810}')
)
SELECT 
 * from i
UNION DISTINCT 
SELECT
 account.* from account join i on i.user_id = account.userid ;

-- 
⚂⚃ 100% natural


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