SQL slower when running for the second time

Hi List,

   I trying to increase performance in my PostgreSQL but there is something
wrong.    when I run this SQL for the first time it takes 1 min. 40 seconds to
return, but when I run it for the second time it takes more than 2 minutes, and
I should retunr faster than the first time.

Does anyone have a advice ?

Atenciosamente,

Rhaoni Chiu Pereira
Sistêmica Computadores

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