limiting the rows to where the sum a column equals a certain value in MySQL

Question

I want to write a query which returns all rows until the sum of one of the columns value reaches a certain value.

For example in the table below:

Answer 1

Here's a way which should work in MySQL :

SELECT
  O.Id,
  O.Type,
  O.MyAmountCol,
  (SELECT
     sum(MyAmountCol) FROM Table1
   WHERE Id <= O.Id) 'RunningTotal'
FROM Table1 O
HAVING RunningTotal <= 7

It involves calculating a running total and selecting records while the running total is less than or equal to the given number, in this case 7.

SQL Fiddle