Sql Query For my case

Question

I Have table in format mentioned below

USER_ID ORDER

1        0
1        1
1        2
1        3
2        0
2        1
2        3
3        0
3        2

I want to find list of user id whose ordering is not continious. i.e userid2(have no ordering of 2) and userid3(having no ordering of 1).

Please help

Answer 1

Assuming there can't be any duplicate order values for a user_id, this should work:

SELECT user_id, max(`order`)-min(`order`)+1 order_range_size, count(*) c
GROUP BY user_id
HAVING c != order_range_size

This doesn't tell you which order is missing from the range; I hope that's OK.