A prepared statement ERROR due to EMPTY_QUERY is defined as a static Instance.

Hi All,

I have found an odd movement when using multiple connections with prepareStatement("").

The following ERROR message appeared.

org.postgresql.util.PSQLException: ERROR: prepared statement "S_1" does not exist

In org/postgresql/core/v3/QueryExecutorImpl.java,
EMPTY_QUERY instance is defined as a static instance.

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private final static SimpleQuery EMPTY_QUERY = new SimpleQuery(new String[] { "" }, null);
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For that reason,
After CONNECTION-A has prepared EMPTY_QUERY already,
If CONNECTION-B tries to execute EMPTY_QUERY for the first time,
then CONNECTION-B sends a bind message to PostgreSQL without prepare.

I attached a sample source and a patch.

Please confirm it.

Best Regards,

Naoya

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Naoya Anzai
Engineering Department
NEC Soft, Ltd.
E-Mail: anzai-naoya(at)mxu(dot)nes(dot)nec(dot)co(dot)jp
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