Max,

It appears you're using MySQL (because I wrote the error message).

If you take a look at the JDBC spec, a JDBC driver _can_ require that
updatable result sets are from queries that reference a single-table,
and that have primary keys, and that the query selects all primary keys.

This is in fact, required when using MySQL, because MySQL doesn't
currently have cursors. For updatable result sets, the JDBC driver has
to be _positively_ sure that it can in fact _uniquely_ identify the row
you are modifying. Without primary keys, this is not possible (in fact,
many other databases that actually have cursors require this as well,
e.g. Oracle is one that immediately comes to mind).

From Section 5.6 of the JDBC-2.0 specification:

"Due to differences in database implementations, the JDBC API does not
specify an exact set of SQL queries which must yield an updatable result
set for JDBC drivers that support updatability. Developers can, however,
generally expect queries which meet the following criteria to produce an
updatable result set:

1. The query references only a single table in the database.

2. The query does not contain any join operations.

3. The query selects the primary key of the table it references.

In addition, an SQL query should also satisfy the conditions listed
below if inserts are to be performed.

4. The query selects all of the non-nullable columns in the underlying
table.

5. The query selects all columns that don’t have a default value."

Regards,

    -Mark