|Subject||Re: [firebird-support] SQL - performance|
> > > The second query has an expression for its search operand, ruling outuse
> > > of the index (for now...expression indices are coming...but theexpression
> > > index would have to exist).Sweeeeeet ;-)
> >On the other hand, a substring(1, x) could be converted to a
> >STARTING WITH as well :-)
> >No need for expression indices there.
> Could be converted to choc-dipped candy, too...but isn't.
The reason I wrote that, is that expression indices aren't needed
for this to be optimized.
I'm not fully aware of what expression indices should be able
to do anyway. I picture usage as UPPER(column) = 'value'
and an Upper(Column) index...
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