[SPARK-20962] Support subquery column aliases in FROM clause

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.1
• Fix Version/s: 2.3.0
• Component/s: SQL
• Assignee: Takeshi Yamamuro
• Reporter: Takeshi Yamamuro
• Created: 02/Jun/17 06:24
• Updated: 29/Jul/17 17:15
• Resolved: 29/Jul/17 17:15

Description

Currently, we do not support subquery column aliases;

scala> sql("SELECT * FROM (SELECT 1 AS col1, 1 AS col2) t(a, b)").show
org.apache.spark.sql.catalyst.parser.ParseException:
mismatched input '(' expecting {<EOF>, ',', 'WHERE', 'GROUP', 'ORDER', 'HAVING', 'LIMIT', 'JOIN', 'CROSS', 'INNER', 'LEFT', 'RIGHT', 'FULL', 'NATURAL', 'LATERAL', 'WINDOW', 'UNION', 'EXCEPT', 'MINUS', 'INTERSECT', 'SORT', 'CLUSTER', 'DISTRIBUTE', 'ANTI'}(line 1, pos 45)


== SQL ==
SELECT * FROM (SELECT 1 AS col1, 1 AS col2) t(a, b)
---------------------------------------------^^^

  at org.apache.spark.sql.catalyst.parser.ParseException.withCommand(ParseDriver.scala:217)
  at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parse(ParseDriver.scala:114)
  at org.apache.spark.sql.execution.SparkSqlParser.parse(SparkSqlParser.scala:48)
  at org.apache.spark.sql.catalyst.parser.AbstractSqlParser.parsePlan(ParseDriver.scala:68)
  at org.apache.spark.sql.SparkSession.sql(SparkSession.scala:623)

We could support this by referring;
http://docs.aws.amazon.com/redshift/latest/dg/r_FROM_clause30.html

Issue Links

• links to: [Github] Pull Request #18185 (maropu)