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12.8 SORT CASES

     SORT CASES BY var_list[({D|A}] [ var_list[({D|A}] ] ...

SORT CASES sorts the active dataset by the values of one or more variables.

Specify BY and a list of variables to sort by. By default, variables are sorted in ascending order. To override sort order, specify (D) or (DOWN) after a list of variables to get descending order, or (A) or (UP) for ascending order. These apply to all the listed variables up until the preceding (A), (D), (UP) or (DOWN).

The sort algorithms used by SORT CASES are stable. That is, records that have equal values of the sort variables will have the same relative order before and after sorting. As a special case, re-sorting an already sorted file will not affect the ordering of cases.

SORT CASES is a procedure. It causes the data to be read.

SORT CASES attempts to sort the entire active dataset in main memory. If workspace is exhausted, it falls back to a merge sort algorithm that involves creates numerous temporary files.

SORT CASES may not be specified following TEMPORARY.