Question

im using JDBC4 (over JDK6) to connect to postgresql 9.0 using their latest JDBC4 driver.

conn = dpaDs.getConnection();
PreparedStatement stmt = conn.prepareStatement("delete from fss where f_id=? and f_lastmodified=?");
UUID target = UUID.fromString("8c5c5ac2-3a2a-49f3-ae48-29226d6ea3e7");
stmt.setObject(1, target, 1111);
//non of these work
//stmt.setNull(2,93);
//stmt.setObject(2,null, 93);
//stmt.setObject(2,null, java.sql.Types.NULL);
//stmt.setNull(2, java.sql.Types.NULL);
int rowCount = stmt.executeUpdate();
int g = 8;

what is the correct way to set the 2nd parameter to null ?
i know that i can use “where … f_lastmodified is null”, but is there no way to get around this?

Answer 1

That won’t work.

NULL comparison cannot be done using the = operator. If you want to test for NULL, you have to use and f_lastmodified IS NULL.

You can’t use a parameter in a prepared statement for an IS NULL condition.