I am overwhelmed by the response ;) If there are no objections I’m going to revert the patch also from master tomorrow.
On 16/6/10, 16:07, "Sergey Shelukhin" <ser...@hortonworks.com> wrote: >There has recently been a change in behavior in Hive wrt doubles and >decimals, HIVE-13380; where the literals were changed to be double by >default, resulting in some unexpected behavior when comparing decimal >columns with arithmetic expressions on literals. >Right now it has been reverted from 2.1, it’s still there on master until >we decide what to do. > >According to SQL92 (I don’t have access to a later one), section 5.3 > <exact numeric literal> ::= <unsigned integer> [ <period> [ <unsigned >integer> ] ] | <period> <unsigned integer> >... >13)The data type of an <exact numeric literal> is exact numeric. > >From previous comments there, exact-numeric would basically be decimal in >this case. > >Approximate (basically, float/double in this case) literal is defined as ><approximate numeric literal> ::= <mantissa> E <exponent> > >Then, in 6.12, the expression (at least the arithmetic) on two exacts >needs to have the exact results; if either side is approximate, the result >is approximate. > >However, some RDBMS-es apparently prefer double over decimal. > >I think we should go according to SQL92, revert the patch also from >master, and also potentially investigate ANSI SQL compatibility for >existing type resolution in other places. >Opinions, suggestions, comments? > > > >
