Re: [Bug] ResultSet#getMetaData() returns null

Nic,

In looking at this some more, I don't think this will be as difficult as
I had feared.  I discovered that ResultSetMetaData doesn't even use the
data that is passed to it, all it needs is the Field[] information.  So
then it just boils down to the following question:  Is the delayed
initialization of the RefCursorResultSet necessary?  If so, I would like
to understand why it is necessary (some comments in the code would
probably be a good thing either way).  This could be fixed in two ways:
1) by removing the delayed initialization altogether, or 2) by adding
the initialization check into the other methods (like getMetaData())
that can be called before next().

thanks,
--Barry

Barry Lind wrote:
> Nic,
>
> Could you look into this bug?  (Let me know either way).  The problem is
>  specific to RefCursorResultSets.  And since you submitted this code, it
> might be easier for you to think of a solution here, even if you don't
> code it.  The problem is that the current logic in
> JdbcXRefCursorResultSet doesn't initialize the ResultSet until next() is
> called.  However the logic in getMetaData() is assuming that the
> ResultSet is already initialized and passes the data and Field[] over. I
> am not really sure how this should work now that RefCursorResultSets are
> in the picture.  Thus I would like your input.
>
> thanks,
> --Barry
>
> PS.  This probably should be added as a test case as well.
>
>
> Doug Kearns wrote:
>
>> Hello all,
>>
>> ResultSet#getMetaData() is returning null, using the current CVS driver,
>> if called before ResultSet#next()
>>
>> <snippet>
>>         db.setAutoCommit(false);
>>
>>         CallableStatement st = db.prepareCall( "{ ? = call doit () }" );
>>         st.registerOutParameter(1, Types.OTHER);
>>
>>         st.execute();
>>         ResultSet rs = (ResultSet) st.getObject(1);
>>
>>         ResultSetMetaData md = rs.getMetaData();
>>         System.out.println( "Column count = " + md.getColumnCount() );
>>     //Exception in thread "main" java.lang.NullPointerException
>>     //at
>> org.postgresql.jdbc2.AbstractJdbc2ResultSetMetaData.getColumnCount(AbstractJdbc2ResultSetMetaData.java:33)
>>
>>     //at JDBCTest.main(JDBCTest.java:16)
>>
>>         rs.next();
>> </snippet>
>>
>> Regards,
>> Doug
>>
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>
>
>
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