EnricoMi commented on code in PR #37407:
URL: https://github.com/apache/spark/pull/37407#discussion_r962542605
##########
sql/catalyst/src/main/antlr4/org/apache/spark/sql/catalyst/parser/SqlBaseParser.g4:
##########
@@ -618,6 +618,46 @@ pivotValue
: expression (AS? identifier)?
;
+unpivotClause
+ : UNPIVOT nullOperator=unpivotNullClause? LEFT_PAREN
+ operator=unpivotOperator
+ RIGHT_PAREN (AS? identifier)?
+ ;
+
+unpivotNullClause
+ : (INCLUDE | EXCLUDE) NULLS
+ ;
+
+unpivotOperator
+ : (unpivotSingleValueColumnClause | unpivotMultiValueColumnClause)
+ ;
+
+unpivotSingleValueColumnClause
+ : unpivotValueColumn FOR unpivotNameColumn IN LEFT_PAREN
unpivotColumns+=unpivotColumn (COMMA unpivotColumns+=unpivotColumn)* RIGHT_PAREN
+ ;
+
+unpivotMultiValueColumnClause
+ : LEFT_PAREN unpivotValueColumns+=unpivotValueColumn (COMMA
unpivotValueColumns+=unpivotValueColumn)* RIGHT_PAREN
+ FOR unpivotNameColumn
+ IN LEFT_PAREN unpivotColumnSets+=unpivotColumnSet (COMMA
unpivotColumnSets+=unpivotColumnSet)* RIGHT_PAREN
+ ;
+
+unpivotColumnSet
+ : LEFT_PAREN unpivotColumns+=unpivotColumn (COMMA
unpivotColumns+=unpivotColumn)* RIGHT_PAREN (AS? identifier)?
Review Comment:
It looks like other systems only allow for identifiers available in the
`FROM`, not expressions as our unpivot supports. In those systems you would
have to move the expressions into a subquery in `FROM` and reference the named
expression.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
