Re: SQL optimization - WHERE SomeField STARTING WITH ...

[Tino Wildenhain <tino@xxxxxxxxxxxxx>]

Bill wrote:
> Tino Wildenhain wrote:
> > Hi Bill,
> >
> > Bill wrote:
> > > The SQL database servers I have worked with cannot use and index for 
> > > a SELECT of the form
> > >
> > > SELECT * FROM ATABLE
> > > WHERE AFIELD LIKE ?
> > >
> > > because there is no way to know the location of the wild card until 
> > > the parameter value is known. InterBase and Firebird allow
> > >
> > > SELECT * FROM ATABLE
> > > WHERE AFIELD STARTING WITH ?
> > >
> > > which is equivalent to LIKE  'ABC%' and will use an index on AFIELD. 
> > > Is there a similar syntax in PostgreSQL?
> >
> > Yes, its actually: LIKE 'ABC%' and it will use an index.
> >
> > Regards
> > Tino
> Are you saying that a parameterized query whose WHERE clause is AFIELD 
> LIKE ? will use an index on AFIELD if the parameter value is 'ABC%'. I 
...
no, I'm not saying that anymore (nor did I intend to do :-) I was just
misreading your question. Sorry.

Regards
Tino

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