select 10 rows per day with order

Question

i have a db with records with date (timestamp) i need to select 10 records for each day (there are many more per day) and order them by few columns...

how should that qu

Answer 1

If you just need ten rows — any ten rows, you don't care which, and there is no guarantee they're random, you can use the LIMIT clause. Example:

SELECT whatever
  FROM tablename
  WHERE datecol = '2009-07-13'
  LIMIT 10

That'll give you ten rows. Its up to MySQL which ten. You can use ORDER BY or additional WHERE items to pick a certain 10. For example, here is the most recent 10:

SELECT whatever
  FROM tablename
  WHERE datecol = '2009-07-13'
  ORDER BY timecol DESC
  LIMIT 10

LIMIT is documented as part of the SELECT syntax.