Re: sql faq
| From: | Dan Anderson | Date: | Wed, 24 Sep 2003 17:11:37 +0000 |
| Subject: | Re: sql faq | ||
| References: | 1 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-163779@lists.php.net to get a copy of this message | ||
On Wed, 2003-09-24 at 12:30, Jonatan Pugliese. wrote:
> select MaeSocio.* from MaeSocio
> LEFT JOIN MaeSeguro ON MaeSocio.NroSocio=MaeSeguro.NroSocio
> where MaeSeguro.NroSocio is null
>
> MaeSeguro.NroSocio is not null
>
> count(*) MaeSocio = 354000
> count(*) MaeSeguro=108000
>
> how i can retype this query?
<Stab in the dark>
SELECT * FROM MaeSocio WHERE ((MaeSocio.NroSocio = MaeSeguro.NroSocio)
AND (NroSocio = NULL));
SELECT * FROM MaeSeguro WHERE MaeSeguro.NroSocio = MaeSocio.NroSocio;
Process the data from there.
Oh, and index MaeSeguro.NroSocio. That will make finding NULL values
easier. I think. :-D
</Stab in the dark>
Let me know if I was right or just...erm...stabbing in the dark.
-Dan