Question

I want to count how many times each user has rows within ‘5’ of eachother.

For example, Don – 501 and Don – 504 should be counted, while Don – 501 and Don – 1600 should not be counted.

Start:

Name        value
_________   ______________
Don         1235
Don         6012
Don         6014
Don         6300
James       9000
James       9502
James       9600
Sarah       1110
Sarah       1111
Sarah       1112
Sarah       1500
Becca       0500
Becca       0508
Becca       0709

Finish:

Name            difference_5
__________      _____________
Don             1
James           0
Sarah           2
Becca           0

Answer 1

Use the ABS() function, in conjunction with a self-join in a subquery:

So, something like:

SELECT name, COUNT(*) / 2 AS difference_5
FROM (
  SELECT a.name name, ABS(a.value - b.value) 
  FROM  tbl a JOIN tbl b USING(name)
  WHERE ABS(a.value - b.value) BETWEEN 1 AND 5
) AS t GROUP BY name

edited as per Andreas’ comment.