Subject | Re: [Firebird-Architect] Inexact database operations |
---|---|

Author | Nando Dessena |

Post date | 2005-06-30T08:03:51Z |

Rick,

R> This has been brought up before. If it were implemented,

R> APPROXIMATE_COUNT would probably always return 42.

I'd try to be a little more pragmatic. Something that returns the

order of magniture of the record count of a huge dataset has its uses.

AFAIK that's what the optimizer does to estimate relation cardinality.

R> There are other solutions to returning an approximate number in a web

R> application.

R> Off the top of my head, the value could be in the response after the

R> results, so that the results are rendered in the browser^H^H^H^H^H^H

R> user-agent, and the total rendered soon after.

R> If it's stateful (due to sessions for example), the value could be

R> updated after the response is sent.

In response? Sure, but who's going to compute it?

Ciao

--

Nando Dessena

http://www.flamerobin.org

R> This has been brought up before. If it were implemented,

R> APPROXIMATE_COUNT would probably always return 42.

I'd try to be a little more pragmatic. Something that returns the

order of magniture of the record count of a huge dataset has its uses.

AFAIK that's what the optimizer does to estimate relation cardinality.

R> There are other solutions to returning an approximate number in a web

R> application.

R> Off the top of my head, the value could be in the response after the

R> results, so that the results are rendered in the browser^H^H^H^H^H^H

R> user-agent, and the total rendered soon after.

R> If it's stateful (due to sessions for example), the value could be

R> updated after the response is sent.

In response? Sure, but who's going to compute it?

Ciao

--

Nando Dessena

http://www.flamerobin.org