The SORTEQOP option
specifies whether the host sort utility accepts the EQUALS option.
(The EQUALS option sorts observations that have duplicate keys in
the original order.) If the utility does accept the EQUALS option,
then SORTEQOP causes the EQUALS option to be passed to it unless you
specify NOEQUALS in the PROC SORT statement. If NOSORTEQOP is in
effect, then the EQUALS option is not passed to the host sort utility
unless you specify the EQUALS option in the PROC SORT statement.
Note that equals processing
is the default for PROC SORT. Therefore, if NOSORTEQOP is in effect,
and if you did not specify EQUALS, then the host sort interface must
do additional processing to ensure that observations with identical
keys remain in their original order. This requirement of the host
system might adversely affect performance.
For information about
specifying the appropriate setting for the SORTEQOP option, see the
documentation for your sort utility.