But how do the user specify custom value for "*"? In the current implementation I am passing "NULL" string to the CubeDimensions constructor. If we need to get that value from user then we need some changes in grammar like
a = CUBE b BY (x,y,z) ALL as "AllProducts"; also what should be the default value if user didn't specify anything? Thanks -- Prasanth On Jun 6, 2012, at 8:41 PM, Dmitriy Ryaboy wrote: > Note that the current CubeDimensions UDF does a third thing -- instead > of rebranding "nulls" as "unknown" and using null to mean "*" or "all > values", the UDF allows you to specify a custom value to stand for "*" > or "all values". That way null can be an individual valid cell value. > > This is (imho) much nicer than the other options, but it does > complicate working with 3rd party tools. > > Does anyone have opinions on this? > > D > > On Wed, Jun 6, 2012 at 2:24 PM, Prasanth J <[email protected]> wrote: >> Hello everyone >> >> I would like to bring up this discussion about the ways for handling NULL >> values in dimensions specified for cubing. For example, if we have a >> dimension color with following values >> >> red >> blue >> null >> green >> >> how do we differentiate if the null value represent rollup of all colors >> values or actual null value? >> >> SQL way: >> There are 2 ways in which SQL server analysis services handles null values >> in dimensions >> 1) Throw error when it encounters null values in dimension values >> 2) Ignore error by adding the null values to UnknownMembers. By default >> UnknownMembers will be named as "Unknown". The name for UnknownMembers can >> also be specified by the user. >> >> Do we need to handle both ways in Pig? I think the first way (throwing >> error) is pretty straightforward. >> For the second way (ignoring error), what is the best way to provide support >> for user specified name for UnknownMembers? >> >> Please share your thoughts about how we can handle this scenario for >> different datatypes in Pig. >> >> Thanks >> -- Prasanth >>
