----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/25564/#review54788 -----------------------------------------------------------
datafu-pig/src/main/java/datafu/pig/util/SelectFieldByName.java <https://reviews.apache.org/r/25564/#comment95058> Hmm, something just occurred to me. This does not currently provide the output schema. So this is one problem. But, how do we determine the output schema? If the output value is decided dynamically, then it can vary. One way to address this is to require that all the other values of the tuple are of the same type. Then you just take the schema form the first value. In your example they are all chararray. But this does limit the uses of this UDF. - Matthew Hayes On Sept. 29, 2014, 12:20 a.m., Russell Jurney wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/25564/ > ----------------------------------------------------------- > > (Updated Sept. 29, 2014, 12:20 a.m.) > > > Review request for DataFu, Jonathan Coveney, Jakob Homan, Matthew Hayes, and > Sam Shah. > > > Repository: datafu > > > Description > ------- > > Example use: > group_fields = LOAD '/e8/smalldata/group_fields.txt' AS > (groupField:chararray); > with_group = CROSS group_fields, hour_rounded; > with_group = FOREACH with_group GENERATE group_fields::groupField AS > groupField, > hour_rounded::sourceNameOrIp AS sourceNameOrIp, > hour_rounded::destinationNameOrIp AS destinationNameOrIp, > ...; > with_value_substitution = FOREACH with_group GENERATE > ChooseFieldByValue(groupField, *) AS groupValue:tuple(value:chararray), *; > with_value_substitution = FOREACH with_value_substitution GENERATE > FLATTEN(groupValue) AS groupValue:chararray, > groupField, > foo, > bar, > ...; > all_success = FOREACH (GROUP with_value_substitution BY (groupField, > groupValue, day)) GENERATE > FLATTEN(group) AS (seriesType, groupValue, day), > (int)COUNT_STAR(with_value_substitution) AS connections:int; > > > Diffs > ----- > > datafu-pig/src/main/java/datafu/pig/util/SelectFieldByName.java > PRE-CREATION > datafu-pig/src/test/java/datafu/test/pig/util/SelectFieldByNameTest.java > PRE-CREATION > > Diff: https://reviews.apache.org/r/25564/diff/ > > > Testing > ------- > > This UDF was used to replace a very inefficient pig script where macros that > did many individual GROUP BY's took many minutes to plan. > > Testing: unit tests and used on real data on a cluster. > > > Thanks, > > Russell Jurney > >
