On Fri, 2006-09-01 at 12:26, Walter Cruz wrote:
> So I can assume that the MySQL implementation is strange? (It accepts
> that kind of query)
Yes, according to the SQL spec, you should generally get an error when
you run a query like this:
select field1, field2 from table group by field1
since you could theoretically get a different value for field2 each time
you run the query. If the data looked like this:
field1 | field2
-------+--------
1 | 1
1 | 3
2 | 5
2 | 3
The possible answers to that query would be (1,1)(2,5), (1,1)(2,3),
(1,3)(2,5), (1,3)(2,3)
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
