Re: What is the number of rows in explain?

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От John A Meinel
Тема Re: What is the number of rows in explain?
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Msg-id 4231AEA1.7070300@arbash-meinel.com
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Ответ на What is the number of rows in explain?  ("Joost Kraaijeveld" <J.Kraaijeveld@Askesis.nl>)
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Joost Kraaijeveld wrote:

>Hi all,
>
>Is the number of rows in explain the number of rows that is expected to be visited or retrieved?
>
>Groeten,
>
>Joost Kraaijeveld
>Askesis B.V.
>Molukkenstraat 14
>6524NB Nijmegen
>tel: 024-3888063 / 06-51855277
>fax: 024-3608416
>e-mail: J.Kraaijeveld@Askesis.nl
>web: www.askesis.nl
>
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>
>
In general, it is the number of rows expected to be retrieved. Since a
Sequential Scan always visits every row, but the rows= number is after
filtering.

John
=:->


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