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Amir Youssefi commented on PIG-750: ----------------------------------- Other use-cases we need have in unit tests: 1) foreach X generate SUM(a) * AVG(b), ... 2) foreach X generate 1 / SUM(a) Currently, there is a work-around suggested to have all algebraic functions calculated in a foreach and then more expressions/mixes are calculated in a second foreach. This way combiner is used in the first foreach and we get combiner speed-up. > Use combiner when a mix of algebraic and non-algebraic functions are used > ------------------------------------------------------------------------- > > Key: PIG-750 > URL: https://issues.apache.org/jira/browse/PIG-750 > Project: Pig > Issue Type: Improvement > Reporter: Amir Youssefi > Priority: Minor > > Currently Pig uses combiner when all a,b, c,... are algebraic (e.g. SUM, AVG > etc.) in foreach: > foreach X generate a,b,c,... > It's a performance improvement if it uses combiner when a mix of algebraic > and non-algebraic functions are used as well. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.