NULLS LAST flag in Denodo, MemSQL, Spark, VectorWise, and XtremeData -

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i doing pseudo-orm personal project, , i'm compiling list of compatibility checks 20+ different sql dialects out there.

currently, doing research on whether dialect supports nulls last flag, i.e. when sorting table, have null come out last item 1, 2, 3, 4, null instead of null, 1, 2, 3, 4.

i have results languages dashdb/mysql/mssql, etc (yes - offer null last) however, following dialects, unable find null-last-ability:

  1. denodo

  2. memsql

  3. spark

  4. vectorwise

  5. xtremedata

a simple "yes" or "no" suffice in answer, however, if write query down on how perform null last operation, great too!

i checked on memsql , afaik nulls last syntax not supported. said, can achieve doing this:

select * foo order ifnull(bar, magic_value) asc

change magic_value sorts last/first depending on data in column. if ok perf hit, can mutate value such if not null value starts prefix sorts high, , if null value sorts lower prefix.

same thing can used implement null first.


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