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From: Blake McBride <blake1024@gmail.com>
Date: Thu, 20 Jul 2023 11:33:10 -0500
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 <CABwHSOurbLHgmvsEzTBRncvFoSt35RU1bs9jvF-287r6dDfD0Q@mail.gmail.com>
Subject: Executing the same query multiple times gets slow
To: pgsql-jdbc@lists.postgresql.org
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Greetings,

I have a complex query that returns about 5,000 records and only a few
columns.  If I run it in psql repeatedly, it's always fast.  If I run it
through JDBC it runs fast at first but then it gets real slow (> 50
seconds).  I can't understand why it would get slow after 30 runs of the
exact same query.

I am running:

Linux / 64GB RAM
PostgreSQL 15.1
postgresql-42.5.4.jar

I am using a prepared statement but a new one each time even though it is
the same query (there are reasons for this).

I found the line that's having the delay is:  pstat.executeQuery();

where:  PreparedStatement pstat;

Sure appreciate any pointers!

Thanks.

Blake

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<div dir=3D"ltr">Greetings,<div><br></div><div>I have a complex query that =
returns about 5,000 records and only a few columns.=C2=A0 If I run it in ps=
ql repeatedly, it&#39;s always fast.=C2=A0 If I run it through=C2=A0JDBC it=
 runs fast at first but then it gets real slow (&gt; 50 seconds).=C2=A0 I c=
an&#39;t understand why it would get slow after 30 runs of the exact same q=
uery.</div><div><br></div><div>I am running:</div><div><br></div><div>Linux=
 / 64GB RAM</div><div>PostgreSQL 15.1</div><div>postgresql-42.5.4.jar<br></=
div><div><br></div><div>I am using a prepared statement but a new one each =
time even though it is the same query (there are reasons=C2=A0for this).</d=
iv><div><br></div><div>I found the line that&#39;s having the delay is:=C2=
=A0 pstat.executeQuery();</div><div><br></div><div>where:=C2=A0 PreparedSta=
tement pstat;</div><div><br></div><div>Sure appreciate any pointers!</div><=
div><br></div><div>Thanks.</div><div><br></div><div>Blake</div><div><br></d=
iv></div>

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