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- From: cortes@enuxva.eas.asu.edu (Enrique Cortes-Rello)
- Newsgroups: comp.databases.ingres
- Subject: prefetchrows
- Message-ID: <1992Dec16.192034.28892@ennews.eas.asu.edu>
- Date: 16 Dec 92 19:20:34 GMT
- Sender: news@ennews.eas.asu.edu (USENET News System)
- Organization: Arizona State University
- Lines: 26
-
- There is an environment variable called
- II_EMBED_SET,that allows programmers to set
- a bunch of features. One of the possible
- actions is:
-
- prefetchrows, that takes the values:
- 0 (default) INGRES decides the number of
- rows to pre-fetch
- 1 disables prefetching
- n specifies the number of rows to be prefetched.
-
- Now, the questions:
-
- (1). What is the meaning of "prefetch" ?
- (2). Is this some buffering mechanism ??
- (3). What are the performance implications?
- (4). How to use?
-
- thanks,
-
- Enrique
-
- ---------------------------------------------------------
- Enrique Cortes-Rello <cortes@asuvax.eas.asu.edu>
- ASU Intelligent Information Systems Lab
- <<< "Aprendiz de todo, oficial de nada" >>>
-