How to delete duplicates in SQL table based on multiple fields
You can try such query:
DELETE FROM table_name AS t1
WHERE EXISTS (
SELECT 1 FROM table_name AS t2
WHERE t2.date = t1.date
AND t2.time = t1.time
AND t2.hometeam_id = t1.hometeam_id
AND t2.awayteam_id = t1.awayteam_id
AND t2.locationcity = t1.locationcity
AND t2.id > t1.id )
This will leave in database only one example of each game instance which has the smallest id.
You should be able to do a correlated subquery to delete the data. Find all rows that are duplicates and delete all but the one with the smallest id. For MYSQL, an inner join (functional equivalent of EXISTS) needs to be used, like so:
delete games from games inner join
(select min(id) minid, date, time,
hometeam_id, awayteam_id, locationcity, locationstate
from games
group by date, time, hometeam_id,
awayteam_id, locationcity, locationstate
having count(1) > 1) as duplicates
on (duplicates.date = games.date
and duplicates.time = games.time
and duplicates.hometeam_id = games.hometeam_id
and duplicates.awayteam_id = games.awayteam_id
and duplicates.locationcity = games.locationcity
and duplicates.locationstate = games.locationstate
and duplicates.minid <> games.id)
To test, replace delete games from games
with select * from games
. Don't just run a delete on your DB :-)