cherrex_DenПонятно, вообще-то это у нас не на что не влияет, но все равно интересно!

даже кейз нашел: http://search.sybase.com/kbx/solvedcases?id_number=11484725

если кто может посмотреть, скажите что там пишут, "официальные" источники

Case Description
GROUP BY sorts data in 12.5.x but does not in 15.0.x. With ASE 15.0.x we have to use SORT BY clause in order to sort the data.

Tip or Workaround
The original sorting of pre-15.0 GROUP BY clause results was actually a side-effect of the GROUP BY processing and not done on purpose. Engineering made some changes with 15.0 that had the side-effect of no longer returning sorted results form GROUP BY clause.

As ANSI standards do not require the results from GROUP BY clause to be sorted, they do not view this as a bug.

However, as users have come to expect sorted results from GROUP BY clause, Engineering created the following CR to implement the pre-150 behavior :

CR424188 When command-line trace flag -T450 is set, queries involving a group-by clause (and having 32 or less distinct group-by columns) will have a predicable ordering similar to that of ASE 12.5.x. Namely, in the absence of an explicit order-by clause, ordering will be that of the group-by columns.

This CR was implemented in 15.0.1 and higher.


Resolution
ANSI standards do not require GROUP BY results to be sorted. Sybase has implemented trace flag -T450 via CR424188 to provide users with the pre-15.0 behavior. This traceflag is available from ASE 15.0.1 and higher.