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Thejas M Nair commented on PIG-1910: ------------------------------------ This can also lead to incorrect query plan, if an alias that occurs after the position corresponding to * projection in schema is used. - {code} grunt> l = load 'x' ; grunt> f = foreach l generate $1 as a, *, $2 as b; grunt> describe f; f: {a: bytearray,(null),b: bytearray} grunt> g = foreach f generate b; grunt> explain g; -- NOTE that alias b is getting translated to column index 2, which is incorrect. ... ... #-------------------------------------------------- # Map Reduce Plan #-------------------------------------------------- MapReduce node scope-20 Map Plan g: Store(fakefile:org.apache.pig.builtin.PigStorage) - scope-19 | |---g: New For Each(false)[bag] - scope-18 | | | Project[bytearray][2] - scope-16 | |---f: New For Each(false,true,false)[bag] - scope-15 | | | Project[bytearray][1] - scope-9 | | | Project[tuple][*] - scope-11 | | | Project[bytearray][2] - scope-13 | |---l: Load(file:///Users/tejas/pig_type/trunk/x:org.apache.pig.builtin.PigStorage) - scope-8-------- Global sort: false ---------------- {code} This problem will also need to be addressed for the range-projection feature in PIG-1693 . > incorrect schema shown when project-star is used with other projections > ----------------------------------------------------------------------- > > Key: PIG-1910 > URL: https://issues.apache.org/jira/browse/PIG-1910 > Project: Pig > Issue Type: Bug > Affects Versions: 0.9.0 > Reporter: Thejas M Nair > Fix For: 0.9.0 > > > {code} > grunt> l = load 'x' ; > grunt> f = foreach l generate $1 as a, *, $2 as b; > grunt> describe f; > f: {a: bytearray,(null),b: bytearray} -- The tuple returned by * is > automatically flattened, so this schema is not correct. It is more accurate > to return a null schema. > {code} -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira