Question

I got players table and host field in it, I also got a second table called bans with the following fields: host, second_host, ip. I need to check if players.host content field is not equal to any of those three fields in the bans table, with one condition: WHERE expiry >= UNIX_TIMESTAMP().

I’ve already built this one, but as you can see, there are three conditions in the bans table, and now I don’t know what to do.

SELECT * FROM players
WHERE host NOT IN (
      SELECT host 
      FROM bans 
      WHERE expires >= UNIX_TIMESTAMP()
)

Now I’d have to do the same for three other fields (second_host and ip). Is that will be possible to do in one query? If so, please post an example.

Answer 1

It’s easiest to do this in a join condition:

SELECT players.*
FROM   players
  LEFT JOIN bans 
    ON players.host IN (bans.host, bans.second_host, bans.ip)
   AND (bans.expires >= UNIX_TIMESTAMP() OR bans.expires = -1)
WHERE  bans.PK IS NULL;  -- use primary key from bans table in place of PK

Learn about SQL joins.