## I'm doing a lot of these, where X is an integer

INSERT INTO deviations(pivot_id, deviant_id, value)
SELECT
  X as pivot_id,
  ratings2.content_id as deviant_id,
  AVG(ratings.rate - ratings2.rate) as value
FROM ratings
INNER JOIN ratings as ratings2
  ON ratings.viewer_id = ratings2.viewer_id
  AND ratings.viewer_type = ratings2.viewer_type
  AND ratings.content_id = X
  AND ratings.content_id < ratings2.content_id
GROUP BY deviant_id

## However I also tried doing a single query for all those IDs:

INSERT INTO deviations(pivot_id, deviant_id, value)
SELECT
  ratings.content_id as pivot_id,
  ratings2.content_id as deviant_id,
  AVG(ratings.rate - ratings2.rate) as value
FROM ratings
INNER JOIN ratings as ratings2
  ON ratings.viewer_id = ratings2.viewer_id
  AND ratings.viewer_type = ratings2.viewer_type
  AND ratings.content_id < ratings2.content_id
GROUP BY pivot_id, deviant_id

## Results in seconds
                                | MANY QUERIES | ONE BIG QUERY |
Default my.cnf values:          |    194       |     267
8MB for max_heap_table_size
and tmp_table_size:             |    367       |     298       |
265MB for max_heap_table_size
and tmp_table_size: 389 seconds |    358       |      78       |

How come using more memory is worse???