Re: Solved, and a bug found! Re: JDBC question: Creating new arrays

Joe Tomcat <tomcat(at)mobile(dot)mp> writes:

> On Tue, 2002-11-12 at 17:39, Doug McNaught wrote:
> > Then you probably need to wrap your Java array in an object that
> > implements java.sql.Array so that the JDBC driver can talk to it.
> > Shouldn't be hard.
>
> That still doesn't make it driver-independent, does it?

How not? Implementing java.sql.Array is the JDBC standard way to do
this, though it seems to be a ridiculous amount of work. Whereas:

> Anyway, I found a simple solution that works easily with Postgres: The
> way PreparedStatement.setArray(Array) works is that it actually gets
> translated to PreparedStatement.setString(Array.toString()). The
> Array.toString() method is very simple; it just makes a string that
> looks like '{484,282,945}' (for an int[]) so I just turned my int[] into
> such a string, and called PreparedStatement.setString(). This is a bit
> of a hack, but it seems that there is no db-independent way to do this,
> so I have no other options. If we need to move to some other db, this
> shouldn't be hard to modify as needed.

This is definitely not driver-independent. ;)

> There is one other problem, though: If I have an array with no
> elements, then this operation:
>
> Array array = resultSet.getArray(3);
> Object o = array.getArray();
>
> throws a Bad Integer exception.

This does sound like a bug.

-Doug