said:
>In the databases I've used the retrieved rows are unordered unless the
>retrieval is via an index.
You and Greg are probably thinking of legacy databases which don't
understand concepts like join. Modern SQL style databases always allow
the result set rows to be sorted, as needed, regardless of whether or not
the column is indexed. What is typically true is that if you don't
specify the sort, the row order is undefined. This is often true even for
selections based on an indexed column. For example in SQL
select indexed_column from table
and
select indexed_column from table order by indexed_column
may order the result set differently.
It is best to think of indexes as performance tuning tools rather than
access tools.
Regards,
Steven
--
----------------------------------------------------------------------
"Steven Levine" MR2/ICE 2.67 #10183 Warp/eCS/DIY/14.103a_W4
www.scoug.com irc.fyrelizard.com #scoug (Wed 7pm PST)
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