Re: SQL Existence Check

[Vernon Hamberg <vhamberg@xxxxxxxxx>]

Ah, yes. But the distinction I meant to make was between index IO and table IO.

Cheers

At 04:44 PM 3/12/02 +0000, you wrote:
>Vernon wrote:
>
> > CHAIN is basically SETLL and READ, so the difference is the
> > time to read the record. Mileage will vary, based on record
> > length and datatypes. What were your fields in the file in
> > question?
>
>Not quite. SETLL will always set the current record pointer. CHAIN will set
>it only when a record is found. If Nathan were to re-run his test where the
>record is never found I think he would find that the CHAINs are quicker
>than the SETLLs.
>
>Dave...
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