Skip to content

[SPARK-17753][SQL] Allow a complex expression as the input a value based case statement #15322

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
hvanhovell wants to merge 2 commits into from
Closed

[SPARK-17753][SQL] Allow a complex expression as the input a value based case statement #15322

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b25c849
Allow a complex expression as the input a value based case statement
hvanhovell Oct 2, 2016
b6b3910
Add support for further case related issue.
hvanhovell Oct 2, 2016
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 6 additions & 6 deletions sql/catalyst/src/main/antlr4/org/apache/spark/sql/catalyst/parser/SqlBase.g4
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -527,16 +527,16 @@ valueExpression
;

primaryExpression
: constant #constantDefault
| name=(CURRENT_DATE | CURRENT_TIMESTAMP) #timeFunctionCall
: name=(CURRENT_DATE | CURRENT_TIMESTAMP) #timeFunctionCall
| CASE value=expression whenClause+ (ELSE elseExpression=expression)? END #simpleCase
| CASE whenClause+ (ELSE elseExpression=expression)? END #searchedCase
| CAST '(' expression AS dataType ')' #cast
| constant #constantDefault
| ASTERISK #star
| qualifiedName '.' ASTERISK #star
| '(' expression (',' expression)+ ')' #rowConstructor
| qualifiedName '(' (setQuantifier? expression (',' expression)*)? ')' (OVER windowSpec)? #functionCall
| '(' query ')' #subqueryExpression
| CASE valueExpression whenClause+ (ELSE elseExpression=expression)? END #simpleCase
| CASE whenClause+ (ELSE elseExpression=expression)? END #searchedCase
| CAST '(' expression AS dataType ')' #cast
| qualifiedName '(' (setQuantifier? expression (',' expression)*)? ')' (OVER windowSpec)? #functionCall
| value=primaryExpression '[' index=valueExpression ']' #subscript
| identifier #columnReference
| base=primaryExpression '.' fieldName=identifier #dereference
Expand Down
2 changes: 1 addition & 1 deletion sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1138,7 +1138,7 @@ class AstBuilder extends SqlBaseBaseVisitor[AnyRef] with Logging {
* }}}
*/
override def visitSimpleCase(ctx: SimpleCaseContext): Expression = withOrigin(ctx) {
val e = expression(ctx.valueExpression)
val e = expression(ctx.value)
val branches = ctx.whenClause.asScala.map { wCtx =>
(EqualTo(e, expression(wCtx.condition)), expression(wCtx.result))
}
Expand Down
4 changes: 4 additions & 0 deletions sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/parser/ExpressionParserSuite.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -292,6 +292,10 @@ class ExpressionParserSuite extends PlanTest {
test("case when") {
assertEqual("case a when 1 then b when 2 then c else d end",
CaseKeyWhen('a, Seq(1, 'b, 2, 'c, 'd)))
assertEqual("case (a or b) when true then c when false then d else e end",
CaseKeyWhen('a || 'b, Seq(true, 'c, false, 'd, 'e)))
assertEqual("case 'a'='a' when true then 1 end",
Copy link
Member

@viirya viirya Oct 3, 2016

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

nit: seems 'a'='a' is a valueExpression? So it should be passed even without this change.

Copy link
Contributor Author

@hvanhovell hvanhovell Oct 3, 2016

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yeah, I thought the same thing. The issue here is that case 'a' also matches the typeConstructor rule which was triggered before the simpleCase rule. So I also fixed this by moving the rules around a bit more.

Copy link
Member

@viirya viirya Oct 3, 2016

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

oh, I see. Currently the first element in typeConstructor is an identifier. Is it too loose?

CaseKeyWhen("a" === "a", Seq(true, 1)))
assertEqual("case when a = 1 then b when a = 2 then c else d end",
CaseWhen(Seq(('a === 1, 'b.expr), ('a === 2, 'c.expr)), 'd))
}
Expand Down