Question

Before I go on, I don’t want to use ANY query which involves selecting all rows and counting the occurrences manually. I’m doing this in PHP by the way.

Basically, I have a bans table. Each new record/row is a new ban. The field titled user_name signifies which player was banned. Is there a way to count who has the most bans in this table? I really don’t want to select every row and then count it out for each player. The table is pretty big, therefore making the mentioned solution impractical and inefficient.

Answer 1

This is done with COUNT() aggregates, grouping by user_name.

Get bans by user from most to least:

SELECT
  user_name,
  COUNT(*) as numbans
FROM bans
GROUP BY user_name
/* ordered by number of bans from greatest to least */
ORDER BY numbans DESC

Get only the most banned user:

SELECT
  user_name,
  COUNT(*) as numbans
FROM bans
GROUP BY user_name
ORDER BY numbans DESC
/* adjust LIMIT for how many records you want returned -- 1 gives only the first record */
LIMIT 1

In your question, you’re very concerned about not wanting to count manually in PHP. Note that this is just about never necessary. RDBMS systems are designed explicitly for organizing and querying data, and are very good at doing tasks like this efficiently. Read up on GROUP BY clauses and aggregate functions in MySQL and master them. You generally shouldn’t need to do it in code.

Bonus: Get all users banned 3 or more times

SELECT
  user_name,
  COUNT(*) as numbans
FROM bans
GROUP BY user_name
/* HAVING clause limits results of an aggregate like COUNT()  (which you cannot do in the WHERE clause) */
HAVING numbans >= 3