在 PreparedStatement 中重用参数？

Question

I am passing a parameter to a PreparedStatement like this :

public void getNodes(String runId, File file, Connection conn) {
    PreparedStatement ps = null;
    ResultSet rs = null;
    try {
        ps = conn.prepareStatement(Mat.queries.get("NettingNode.QUERY"));

        ps.setString(1, runId);
        ps.setFetchSize(10000);
        rs = ps.executeQuery();

        // etc.
    } catch (Exception e) {
        logger.error(e, e);
    } finally {
        close(rs, ps);
    }
}

And the query looks like this :

select * from table_1 where run_id = ?

Now I want to modify my query like this, and reuse the first parameter (both ? would use the runId parameter) :

select * from table_1 where run_id = ?
union
select * from table_2 where run_id = ?

Is that possible without doing this :

ps.setString(1, runId);
ps.setString(2, runId);

Answer 1

This cannot be done with plain JDBC. You could instead use Spring's JDBCTemplate, which would support what you want with Named Parameters, and re-use the same name wherever it's needed in the statement.

See Named parameters in JDBC

Answer 2

The following works fine with oracle. However it may not be a good choice if the tables are huge.

Select * from ( SELECT ? run_id FROM DUAL ) A
JOIN (  select * from table_1
        union
        select * from table_2 
     ) B ON A.run_id = B.run_id