HyukjinKwon opened a new pull request #27601: [SPARK-30847][SQL] Take productPrefix into account in MurmurHash3.productHash URL: https://github.com/apache/spark/pull/27601 ### What changes were proposed in this pull request? This PR proposes to port Scala's bug fix https://github.com/scala/scala/pull/7693 (Scala 2.13) to fix https://github.com/scala/bug/issues/10495 issue. In short, it is possible for different product instances having the same children to have the same hash. See: ```scala scala> spark.range(1).selectExpr("id - 1").queryExecution.analyzed.semanticHash() res0: Int = -565572825 scala> spark.range(1).selectExpr("id + 1").queryExecution.analyzed.semanticHash() res1: Int = -565572825 ``` ### Why are the changes needed? It was found during the review of https://github.com/apache/spark/pull/27565; however, I suspect this can potentially be correctness issue. ### Does this PR introduce any user-facing change? Possibly yes; however, it's not identified yet. See ### How was this patch tested? Manually tested, and unittest was added.
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