Re: JDBC setTimestamp question - Mailing list pgsql-jdbc

I checked the source code and inside the method org.postgresql.jdbc.PgPreparedStatement.setTimestamp(int, Timestamp, Calendar) I found the code I was interesting to:

int oid = Oid.UNSPECIFIED;

// Use UNSPECIFIED as a compromise to get both TIMESTAMP and TIMESTAMPTZ working.

// This is because you get this in a +1300 timezone:

//

// template1=# select '2005-01-01 15:00:00 +1000'::timestamptz;

// timestamptz

// ------------------------

// 2005-01-01 18:00:00+13

// (1 row)

// template1=# select '2005-01-01 15:00:00 +1000'::timestamp;

// timestamp

// ---------------------

// 2005-01-01 15:00:00

// (1 row)

// template1=# select '2005-01-01 15:00:00 +1000'::timestamptz::timestamp;

// timestamp

// ---------------------

// 2005-01-01 18:00:00

// (1 row)

// So we want to avoid doing a timestamptz -> timestamp conversion, as that

// will first convert the timestamptz to an equivalent time in the server's

// timezone (+1300, above), then turn it into a timestamp with the "wrong"

// time compared to the string we originally provided. But going straight

// to timestamp is OK as the input parser for timestamp just throws away

// the timezone part entirely. Since we don't know ahead of time what type

// we're actually dealing with, UNSPECIFIED seems the lesser evil, even if it

// does give more scope for type-mismatch errors being silently hidden.

// If a PGTimestamp is used, we can define the OID explicitly.

if (t instanceof PGTimestamp) {

PGTimestamp pgTimestamp = (PGTimestamp) t;

if (pgTimestamp.getCalendar() == null) {

oid = Oid.TIMESTAMP;

} else {

oid = Oid.TIMESTAMPTZ;

cal = pgTimestamp.getCalendar();

}

}

if (cal == null) {

cal = getDefaultCalendar();

}

bindString(i, getTimestampUtils().toString(cal, t), oid);

I saw that I can use PGTimestamp instead of sql Timestamp.

In that case all works fine.

Anyway I do not fully understand the comment and why we set oid = Oid.UNSPECIFIED; in case of normal sql Timestamp.

Is there any different between a java.sql.Timestamp.Timestamp and org.postgresql.util.PGTimestamp.PGTimestamp ?

Cannot be use oid = Oid.TIMESTAMP in any other case as when t is not an instance of PGTimestamp?

Thanks

Renzo