[GitHub] spark pull request #15427: [SPARK-17866][SPARK-17867][SQL] Fix Dataset.dropd...
Github user asfgit closed the pull request at: https://github.com/apache/spark/pull/15427 --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- - To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
[GitHub] spark pull request #15427: [SPARK-17866][SPARK-17867][SQL] Fix Dataset.dropd...
Github user viirya commented on a diff in the pull request: https://github.com/apache/spark/pull/15427#discussion_r83140093 --- Diff: sql/core/src/main/scala/org/apache/spark/sql/Dataset.scala --- @@ -1878,17 +1878,25 @@ class Dataset[T] private[sql]( def dropDuplicates(colNames: Seq[String]): Dataset[T] = withTypedPlan { val resolver = sparkSession.sessionState.analyzer.resolver val allColumns = queryExecution.analyzed.output -val groupCols = colNames.map { colName => - allColumns.find(col => resolver(col.name, colName)).getOrElse( +val groupCols = colNames.flatMap { colName => + // It is possibly there are more than one columns with the same name, + // so we call filter instead of find. + val cols = allColumns.filter(col => resolver(col.name, colName)) + if (cols.isEmpty) { throw new AnalysisException( --- End diff -- My thought is: When an user mistakenly gives wrong column to `Dataset.drop`, it can be easily found out. But for `Dataset.dropDuplicates`, it might be harder to figure out duplicate rows are still there. So to throw an explicit exception looks more proper to me. --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- - To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
[GitHub] spark pull request #15427: [SPARK-17866][SPARK-17867][SQL] Fix Dataset.dropd...
GitHub user viirya opened a pull request: https://github.com/apache/spark/pull/15427 [SPARK-17866][SPARK-17867][SQL] Fix Dataset.dropduplicates ## What changes were proposed in this pull request? Two issues regarding Dataset.dropduplicates: 1. Dataset.dropDuplicates should consider the columns with same column name We find and get the first resolved attribute from output with the given column name in `Dataset.dropDuplicates`. When we have the more than one columns with the same name. Other columns are put into aggregation columns, instead of grouping columns. 2. Dataset.dropDuplicates should not change the output of child plan We create new `Alias` with new exprId in `Dataset.dropDuplicates` now. However it causes problem when we want to select the columns as follows: val ds = Seq(("a", 1), ("a", 2), ("b", 1), ("a", 1)).toDS() // ds("_2") will cause analysis exception ds.dropDuplicates("_1").select(ds("_1").as[String], ds("_2").as[Int]) Because the two issues are both related to `Dataset.dropduplicates` and the code changes are not big, so submitting them together as one PR. ## How was this patch tested? Jenkins tests. You can merge this pull request into a Git repository by running: $ git pull https://github.com/viirya/spark-1 fix-dropduplicates Alternatively you can review and apply these changes as the patch at: https://github.com/apache/spark/pull/15427.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #15427 commit dd6405c003ea082b1c614f2efed4d1bcb2d6f5b9 Author: Liang-Chi Hsieh Date: 2016-10-11T06:08:44Z Fix Dataset.dropduplicates. --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- - To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org