How to select rows that don't have value in a second table
Basically I have a main table (accounts) and a meta table (accounts_meta)... The meta table looks like this:
id | account_id | meta_key | meta_value
What I want to do is only select accounts that do not have 'referrer_paid' as a row in the accounts_meta table...
Here is my cod开发者_Go百科e so far...
SELECT a.* FROM accounts AS a
LEFT JOIN accounts_meta AS am ON a.id = am.account_id AND am.meta_key != 'referrer_paid'
WHERE a.account_referrer != ''
GROUP BY a.id
Hopefully I am making sense. What am I doing wrong?
tiny change from @lexu:
SELECT * FROM accounts WHERE id NOT IN ( select account_id from `account_meta_table` where meta_key = 'referrer_paid' );
SELECT *
FROM accounts
WHERE id NOT IN ( select DISTINCT account_id
from `account_meta_table`
where meta_key != 'referrer_paid'
);
SELECT a.* FROM accounts AS a
LEFT JOIN accounts_meta AS am ON a.id = am.account_id AND am.meta_key = 'referrer_paid'
WHERE a.account_referrer != ''
AND am.account_id IS NULL
you dont need group by as left-join-is-null don't produce duplicate account rows
EDIT: duh, changed am.meta_key != 'referrer_paid'
to am.meta_key = 'referrer_paid'
This is what you wanted. It returns NULL for joined row if it doesnt match and you only take NULL rows
SELECT a.* FROM accounts AS a LEFT JOIN accounts_meta AS am ON a.id = am.account_id AND am.meta_key != 'referrer_paid' WHERE ISNULL(am.account_referrer) GROUP BY a.id
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