What do the numbers refer to in
GROUP BY and
ORDER BY clauses?
The numbers are a way to refer to the columns in the
SELECT statement (ie.
1 is the first column selected,
2 is the second column selected, etc). For example, this:
SELECT col_A, col_B FROM tbl ORDER BY col_A;
is equivalent to:
SELECT col_A, col_B FROM tbl ORDER BY 1;