How mysql order the rows with same values

Question

In my database I have some records where I am sorting by what happens to be the same value:

| col1 | timestamp              |
| row1 | 2011-07-01 00:00:00            


        

Answer 1

Lot's of answers already, but the bottom line answer is NO.

If you want rows returned in a particular sequence, consistently, then specify that in an ORDER BY. Without that, there absolutely NO GUARANTEE what order rows will be returned in.

I think what you may be missing is that there can be multiple expressions listed in the ORDER BY clause. And you can include expressions that are not in the SELECT list.

In your case, for example, you could use ORDER BY timestamp, id.

(Or some other columns or expressions.)

That will order the rows first on timestamp, and then any rows that have the same value for timestamp will be ordered by id, or whatever the next expression in this list is.