[ https://issues.apache.org/jira/browse/SPARK-17114?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Apache Spark reassigned SPARK-17114: ------------------------------------ Assignee: Apache Spark > Adding a 'GROUP BY 1' where first column is literal results in wrong answer > --------------------------------------------------------------------------- > > Key: SPARK-17114 > URL: https://issues.apache.org/jira/browse/SPARK-17114 > Project: Spark > Issue Type: Bug > Affects Versions: 1.6.2, 2.0.0 > Reporter: Josh Rosen > Assignee: Apache Spark > Labels: correctness > > Consider the following example: > {code} > sc.parallelize(Seq(128, 256)).toDF("int_col").registerTempTable("mytable") > // The following query should return an empty result set because the `IN` > filter condition is always false for this single-row table. > val withoutGroupBy = sqlContext.sql(""" > SELECT 'foo' > FROM mytable > WHERE int_col == 0 > """) > assert(withoutGroupBy.collect().isEmpty, "original query returned wrong > answer") > // After adding a 'GROUP BY 1' the query result should still be empty because > we'd be grouping an empty table: > val withGroupBy = sqlContext.sql(""" > SELECT 'foo' > FROM mytable > WHERE int_col == 0 > GROUP BY 1 > """) > assert(withGroupBy.collect().isEmpty, "adding GROUP BY resulted in wrong > answer") > {code} > Here, this fails the second assertion by returning a single row. It appears > that running {{group by 1}} where column 1 is a constant causes filter > conditions to be ignored. > Both PostgreSQL and SQLite return empty result sets for the query containing > the {{GROUP BY}}. -- 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