Subject RE: [firebird-support] Re: Compound Index
Author Mercea Paul
>I thought so. I have a hypothesis. Perhaps Ann or Helen can comment.
>I think this might be related to MGA. When FB receives my SQL
>statement (select first 10 * from MY_TABLE where Column1 > 100 order by
>Column1, Column2), it doesn't use the parameter for FIRST. So it will
>tag all the 89901 records with my transaction id. This essentially is
>equivalent to a table scan. The parameter for FIRST is only used in
>the output stage to restrict the number of records returned.

If you have:
Select col1, col2 from mytable
Order by col1

I thing is normal to parse all table to create ordered field for col1.
If you need first 10, is normal to parse all table (column col1) to put data
in that order and show only first 10 from them.