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Yin Huai edited comment on SPARK-10429 at 9/12/15 10:37 PM: ------------------------------------------------------------ [Here | https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/codegen/GenerateMutableProjection.scala#L41-L66] and [here | https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/Projection.scala#L79-L87] are places that needs to be changed. was (Author: yhuai): [Here | https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/codegen/GenerateMutableProjection.scala#L41-L66] is the code block that needs to be changed. > MutableProjection should evaluate all expressions first and then update the > mutable row > --------------------------------------------------------------------------------------- > > Key: SPARK-10429 > URL: https://issues.apache.org/jira/browse/SPARK-10429 > Project: Spark > Issue Type: Sub-task > Components: SQL > Reporter: Yin Huai > Priority: Blocker > > Right now, SQL's mutable projection updates every value of the mutable > project after it evaluates the corresponding expression. This makes the > behavior of MutableProjection confusing and complicate the implementation of > common aggregate functions like stddev because developers need to be aware > that when evaluating {{i+1}}th expression of a mutable projection, {{i}}th > slot of the mutable row has already been updated. > A better behavior of MutableProjection will be that we evaluate all > expressions first and then update all values of the mutable row. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org