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Re: [JDBC] JDBC causing the connection to close after executing a COPY command

From: Altaf Malik <mmalik_altaf(at)yahoo.com>
Date: Thu Dec 13 2007 - 14:09:49 EST

I debugged little more and found that this is not because of incomplete copy support. When a response to any of the copy operations is received, JDBC reads next few bytes to ignore the response. But unfortunately driver reads extra four bytes which is the RFQ message so the RFQ message gets corrupted and IOException is thrown considering it as an unknown packet.

I am attaching a patch that fixes this issue and driver works smoothly even after giving the error on copy response.

Regards,
Altaf Malik
EnterpriseDB
http://www.enterprisedb.com/

Kris Jurka <books@ejurka.com> wrote:

On Thu, 13 Dec 2007, Altaf Malik wrote:

> Also if i enable logging in JDBC, and only execute the COPY statement,
> log shows that FrontEnd sent a Terminate message.
>

What's happening is that after receiving the server's message that it wants to do a COPY, the driver doesn't understand the protocol and dies with an "java.io.IOException: Unexpected packet type: " error. Once this happens the driver can't do anything but close the connection. As part of the connection closing process it issues a Terminate message to the server, in case it's still listening and the protocol is in a good enough state that the server might receive it. The driver is not explicitly terminating the connection upon receiving a copy request, that's just what happens when it gets confused.

Kris Jurka

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Received on Thu Dec 13 14:11:06 2007

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