Curious, I ran this one using set explain:
SELECT MIN(colno) FROM syscolumns WHERE colno>=3D1 AND colno>1
Estimated Cost: 400
Estimated # of Rows Returned: 1
1) informix.syscolumns: INDEX PATH
(1) Index Keys: tabid colno (Key-Only)
Index Key Filters: (informix.syscolumns.colno >=3D 1 )
The AND is being dropped. It would seem that the optimizer looks for
simpli=
fications that can be applied and in this case is dropping the more
restrit=
ive filter. Of course I could be giving the optimizer too much credit.
> -----Original Message-----
> From: informix-list-bounces@[EMAIL PROTECTED]
> [mailto:informix-list-bounces@[EMAIL PROTECTED]
Behalf Of Andrew Ford
> Sent: Wednesday, May 07, 2008 10:59 AM
> To: informix-list@[EMAIL PROTECTED]
> Subject: Re: reliability?
>=20
>=20
> > Same on HPUX 11.11, IDS10.00.FC6
> >
>=20
> Not the same result on IDS 11.10.UC1, Red Hat Enterprise=20
> Linux ES release 4.
>=20
> > echo "SELECT MIN(colno) FROM syscolumns WHERE colno>=3D1 AND=20
> colno>1" |=20
> > dbaccess sysmaster
>=20
> Database selected.
>=20
>=20
>=20
> (min)
>=20
> 2
>=20
> 1 row(s) retrieved.
>=20
>=20
>=20
> Database closed.
>=20
>=20
> Andrew=20
>=20
>=20
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> Informix-list mailing list
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>=20
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