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List:       mysql
Subject:    Re: A Simple Query Help
From:       Igor Shevtsov <nixofortune () gmail ! com>
Date:       2012-04-22 21:45:27
Message-ID: 4F947BF7.4050903 () googlemail ! com
[Download RAW message or body]

Hi Rafael,
You can try using correlated subquery instead of outer join. This can be slow with \
big tables though:

SELECT * FROM users WHERE accept_email = 1 and email not in (SELECT email FROM \
                sent_emails WHERE sent_emails
.email = users.email AND messageID NOT LIKE = ‘XXXXXX’) 

OR OUTER JOIN as a better option:

SELECT u.* FROM users AS u OUTER LEFT JOIN sent_emails AS se USING (email) where \
u.accept_email = 1 AND se.messageID NOT LIKE = ‘XXXXXX’ AND se.email IS NULL



Thanks,
Egor




SELECT * FROM sent_emails WHERE email in (SELECT email FROM users WHERE accept_email \
= 1) AND messageID NOT LIKE = ‘XXXXXX’



On 04/22/2012 09:30 PM, Rafael Ribeiro wrote:
> Dear Friends,
> 
> 
> 
> I m new on this list, and I m trying to learn more about mysql.
> 
> 
> 
> After perform a lot of searchs in the Internet, I have no answer to my
> question and would like to ask your help.
> 
> 
> 
> I wanna a perform a query that depends of the result from another (query)
> table inside the same database.
> 
> 
> 
> On this scenario:
> 
> 
> 
> I have 02 tables:
> 
> 
> 
> Table 1 => users
> 
> Table 2 => sent_emails
> 
> 
> 
> 
> 
> I wanna select ONLY the users that are NOT inside the table SENT_emails
> 
> 
> 
> Example:
> 
> 
> 
> $query1 = SELECT * FROM users WHERE accept_email = ‘1’ 
> 
> 
> 
> The results from query above SHOULD depends of the query Bellow:
> 
> 
> 
> $query2 = SELECT * FROM sent_emails WHERE email = $email_from_query_above
> AND messageID NOT LIKE = ‘XXXXXX’
> 
> 
> 
> The results of the first query, should display only the users that are NOT
> inside the condition of query 2.
> 
> 
> 
> I read about INNER JOIN LEFT ... but I can´t understand ...
> 
> 
> 
> Can help me?
> 
> 
> 
> With Regards,
> 
> Rafael Ribeiro
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 

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