[ https://issues.apache.org/jira/browse/SPARK-28477?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Wenchen Fan resolved SPARK-28477. --------------------------------- Fix Version/s: 3.0.0 Resolution: Fixed Issue resolved by pull request 26294 [https://github.com/apache/spark/pull/26294] > Rewrite `CASE WHEN cond THEN ifTrue OTHERWISE ifFalse` END into `IF(cond, > ifTrue, ifFalse)` > ------------------------------------------------------------------------------------------- > > Key: SPARK-28477 > URL: https://issues.apache.org/jira/browse/SPARK-28477 > Project: Spark > Issue Type: Improvement > Components: Optimizer, SQL > Affects Versions: 3.0.0 > Reporter: Josh Rosen > Priority: Major > Fix For: 3.0.0 > > > Spark SQL has both {{CASE WHEN}} and {{IF}} expressions. > I've seen many cases where end-users write > {code:java} > when(x, ifTrue).otherwise(ifFalse){code} > because Spark doesn't have a {{org.apache.spark.sql.functions._}} method for > the {{If}} expression. > Unfortunately, {{CASE WHEN}} generates substantial code bloat because its > codgen is implemented using a {{do-while}} loop. In some performance-critical > frameworks, I've modified our code to directly construct the Catalyst {{If}} > expression, but this is toilsome and confusing to end-users. > If we have a {{CASE WHEN}} which has only two branches, like the example > given above, then Spark should automatically rewrite it into a simple {{IF}} > expression. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org