How can I count something before inserting? - mysql

Question

I have this table:
// cookies
+---------+-------------------------+------------------+------------+
| id | email | cookie | date_time |
+---------+-------------------------+------------------+------------+
| int(11) | varchar(50) | varchar(128) | int(11) |
+---------+-------------------------+------------------+------------+
| 1 | jack_2009#gmail.com | ojer0f934mf2... | 1467204523 |
| 2 | peter.zm#yahoo.com | ko4398f43043... | 1467205521 |
| 3 | matrix_john23#gmail.com | 34fjkg3j438t... | 1467205601 |
| 4 | peter.zm#yahoo.com | 0243hfd348i4... | 1467206039 |
+---------+-------------------------+------------------+------------+
And here is my query:
INSERT INTO cookies VALUES(NULL, $email, $hash, unix_timestamp())
Now I need to check following condition before inserting:
The number of rows (for specific user) should be less than:
5 per hour
10 per day
50 per month
100 per total
I just can check the last case:
INSERT INTO cookies(id, email, cookie, date_time)
SELECT NULL, $email, $hash, unix_timestamp()
FROM cookie
WHERE email = $email AND
100 >= ( SELECT count(1) FROM cookies WHERE email = $email )
Well, how can I add other conditions?

Answer 1

I'm not positive on whether the >'s (in the group by) should be >='s, but I think this will do what you are asking.
INSERT INTO cookies(id, email, cookie, date_time)
SELECT NULL, $email, $hash, unix_timestamp()
FROM cookie
WHERE email = $email
AND NOT EXISTS (
SELECT COUNT(CASE WHEN date_time > UNIX_TIMESTAMP(now() - INTERVAL 1 HOUR)
THEN 1 ELSE NULL END) AS rowsInLastHour
, COUNT(CASE WHEN date_time > UNIX_TIMESTAMP(now() - INTERVAL 1 DAY)
THEN 1 ELSE NULL END) AS rowsInLastDay
, COUNT(CASE WHEN date_time > UNIX_TIMESTAMP(now() - INTERVAL 1 MONTH)
THEN 1 ELSE NULL END) AS rowsInLastMonth
, COUNT(1) AS rowsEver
FROM cookie
WHERE email = $email
HAVING rowsInLastHour > 5
OR rowsInLastDay > 10
OR rowsInLastMonth > 50
OR rowsEver > 100
)
;
It counts all the rows (for the email) that had date_time values in the last hour|day|month by using now() - INTERVAL 1 HOUR|DAY|MONTH to find when the last hour|day|month started, and counting those values that occurred after those starting times.
It then uses the HAVING to only yield the singular result (aggregation such as COUNT that does not have an associated GROUP BY clause always results in 1 row), if any of the limits you specified were exceeded.
Then the NOT EXISTS returns true if there were no results (because the limits were not exceeded).
Edit: Updated comparisons to use unit timestamps, as needed by question.

Answer 2

You can use stored procedure and within that you can handle this. Pass your insert values to this stored procedure
DELIMITER $$
CREATE PROCEDURE `sp_test`(id int, email varchar(45), cookie varchar(45), date_time datetime)
BEGIN
DECLARE countval INT;
SET countval = (SELECT sum(1) FROM cookies WHERE email = $email );
IF (countval is null) THEN
// do something
ELSEIF (countval>10) THEN
// do something like that
ELSE
// do something
END IF;
// insert query
END $$
DELIMITER ;