Re: execution time

Valentina Tedone <valetedo88(at)gmail(dot)com> writes:
> The problem is about time, infact to solve i.e. this query:

> "SELECT * FROM data d WHERE d.type = 7 AND
> (((d.metadata->'chromosome'->>'value')::text IN ('3','7')) AND
> ((d.metadata->'somatic'->>'value')::boolean = 'true')) and
> ((d.metadata->'filter'->>'value')::text IN ('pass')) LIMIT 30;"

> the first db has an average time about 52.876 ms, the second about
> 470.1172 ms and the bigger one about 58.3572 ms.

> Why is there this difference?it is only for the different strategy?

You have not provided enough detail to let anyone do more than guess.
There is advice here about how to ask answerable questions:
https://wiki.postgresql.org/wiki/Slow_Query_Questions

regards, tom lane