Обсуждение: SQL -select count-

when I do :

select count(column_name) from table_name

should I get the count for all columns or just those which are not null?
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On Tuesday 19 Nov 2002 5:06 pm, Giannis wrote:
> when I do :
>
> select count(column_name) from table_name
>
> should I get the count for all columns or just those which are not null?

Just "not null" - use count(*) or count(0) for a count of rows.

--  Richard Huxton

On Tue, 19 Nov 2002, Giannis wrote:

> when I do :
>
> select count(column_name) from table_name
>
> should I get the count for all columns or just those which are not null?

Γιάννη,
θα πάρεις το πλήθος των κολόνων !! που δεν είναι null.

Γιατι δεν κάνεις ένα τέστ μόνος?

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