Question

I have this table :

TICKETID | PRICE | NUMBER

So for each ticketid, the player can pay a price for each number on the ticketid.

So if the player wants to pay 1$, 3$ and 4$ for numbers 22,23 and 24 for ticketid 25, then the table will look like this :

TICKETID | PRICE | NUMBER 
25       |   1   |  22 
25       |   3   |  23 
25       |   4   |  24

I want to select a random ticket that has TOTAL PRICE >50, to make it receive a prize.

I also want that the randomization to be fair, and that when doing this draw, each ticket would have only 1 apparition rate. If I don’t use DISTINCT or GROUPBY, then a ticketid with 10 numbers will have more chances to get drawn than a ticket with 2 numbers.

I tried this but it’s not working:

SELECT DISTINCT(ticketid),SUM(price) FROM table 
     WHERE SUM(price)>50 GROUP BY ticketid

I get the error message

invalid usage of GROUP BY function

Can anybody help?

Answer 1

What you want is the “HAVING” clause which is applied to any possible candidate records AFTER the group by aggregations have been processed. The Having is applied THEN and either included (or not) in the final result set.

SELECT 
      ticketid,
      SUM(price) TotalPrice
   FROM 
      table 
   group by
      TicketID
   HAVING
      sum(price) > 50