Re: Fwd: [JDBC] Re: 9.4-1207 behaves differently with server side prepared statements compared to 9.2-1102 - Mailing list pgsql-hackers

From Vladimir Sitnikov
Subject Re: Fwd: [JDBC] Re: 9.4-1207 behaves differently with server side prepared statements compared to 9.2-1102
Date
Msg-id CAB=Je-FzFg-gKq8RUkEiXG=XDcXwoZa+Rn8o7XzwNjjJ3_rNJA@mail.gmail.com
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In response to Re: Fwd: [JDBC] Re: 9.4-1207 behaves differently with server side prepared statements compared to 9.2-1102  (Pavel Stehule <pavel.stehule@gmail.com>)
Responses Re: Fwd: [JDBC] Re: 9.4-1207 behaves differently with server side prepared statements compared to 9.2-1102
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VS>>Why doesn't backend reuse already existing good plan?
PS>this logic is driven by plan cost, not by plan execution time.

It do understand that currently PG replans with $1, $2 and uses
default selectivities for that.

What I am asking is to make PG aware of "previously used bind values",
so it would calculate proper selectivities for $1, $2.

PS. It is not the first time the problem bites me, so I hand-crafted a testcase.

Vladimir



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