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From: Xikui Wang <xikuiw@uci.edu>
Date: Tue, 19 Mar 2019 18:09:22 -0700
Message-ID: 
 <CAN-bgPqznO45pHHcvnOQG0YQAN6ksjTEv1Q4s_mBWg02u4gTxg@mail.gmail.com>
Subject: Implicit query plan caching within a connection
To: psycopg@lists.postgresql.org
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Hi Devs,

I'm working on a performance test using Psycopg2 + Postgres. My workload is
to do a spatial join to use one data point joining two reference tables by
repeatedly issuing a query string with different coordinates. The average
query execution time that I got is 0.5 ms, which is surprisingly fast. I
started a pgsql terminal and analyzed the same query multiple times. The
overall execution time is around 1.5ms with ~1ms in planning and 0.5ms in
execution. That makes me is that because psycopg2 implicitly cached the
plan. Is there any implicit optimization there? Thanks in advance!

Best,
Xikui

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<div dir=3D"ltr">Hi Devs,<div><br></div><div>I&#39;m working on a performan=
ce test using Psycopg2=C2=A0+ Postgres. My workload is to do a spatial join=
 to use one data point joining two reference tables by repeatedly issuing a=
 query string with different coordinates. The average query execution time =
that I got is 0.5 ms, which is surprisingly fast. I started a pgsql=C2=A0te=
rminal and analyzed the same query multiple times. The overall execution ti=
me is around 1.5ms with ~1ms in planning and 0.5ms in execution. That makes=
 me is that because psycopg2 implicitly cached the plan. Is there any impli=
cit optimization there? Thanks in advance!</div><div><br></div><div>Best,</=
div><div>Xikui</div></div>

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