MySQL不在或不是REGEXP

Question

I have 2 tables: voters , banned_domains I want to get all the votes except where banned domains This query works well

SELECT * FROM `voters` email NOT REGEXP('tempmail.com|tempmail.org')

I want to compare with the request to another table, but this code does not work:

SELECT * FROM `voters` email NOT IN(SELECT domain FROM banned_domains)

Thanks a lot

UPDATE : I apologize for the incomplete data. In the voters I have a full email address example 'oleole@mail.com' but in the banned_domains i have only domain names example 'mail.com'

I changed the query, but it does not work

SELECT * FROM  voters
WHERE DISTINCT RIGHT(  voters.email , LENGTH(  voters.email ) - LOCATE(  '@', voters.email ) ) NOT IN (SELECT domain FROM banned_domains)

ERROR:#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DISTINCT RIGHT(  voters.email , LENGTH(  voters.email ) - LOCATE(  '@', voters.e' at line 2 

Answer 1

You are missing where in your query change

SELECT * FROM `voters` email NOT IN(SELECT domain FROM banned_domains)

to

SELECT * FROM `voters` WHERE email NOT IN(SELECT domain FROM banned_domains)

Answer 2

You need to perform a REGEXP match between the email and domain, but NOT IN performs an exact match.

SELECT v.*
FROM voters AS v
LEFT JOIN banned_domains AS d ON v.email REGEXP d.domain
WHERE d.domain IS NULL

Answer 3

A typical reason for this would be that domain takes on NULL values. You can fix this by explicitly filtering these out:

SELECT *
FROM `voters`
WHERE email NOT IN (SELECT domain FROM banned_domains WHERE domain is not null);

However, I prefer using NOT EXISTS , because the semantics are more what people expect:

SELECT v.*
FROM `voters` v
WHERE NOT EXISTS (SELECT 1 FROM banned_domains bd WHERE bd.domain = v.domain);

NOTE: I assume the issue is not the missing where clause, because you claim the first query works.