Add rollup() and cube() for group by clause

This syntax is supported on at least DB2, Oracle, SQL Server, and
Postgres. It's not supported on MySQL.

hibernate-core/src/main/antlr/org/hibernate/grammars/hql/HqlLexer.g4

@@ -157,6 +157,7 @@ COLLATE				: [cC] [oO] [lL] [lL] [aA] [tT] [eE];
 CONCAT				: [cC] [oO] [nN] [cC] [aA] [tT];
 COUNT				: [cC] [oO] [uU] [nN] [tT];
 CROSS				: [cC] [rR] [oO] [sS] [sS];
+CUBE				: [cC] [uU] [bB] [eE];
 CURRENT				: [cC] [uU] [rR] [rR] [eE] [nN] [tT];
 CURRENT_DATE		: [cC] [uU] [rR] [rR] [eE] [nN] [tT] '_' [dD] [aA] [tT] [eE];
 CURRENT_INSTANT		: [cC] [uU] [rR] [rR] [eE] [nN] [tT] '_' [iI] [nN] [sS] [tT] [aA] [nN] [tT]; //deprecated legacy
@@ -246,6 +247,7 @@ POWER				: [pP] [oO] [wW] [eE] [rR];
 QUARTER				: [qQ] [uU] [aA] [rR] [tT] [eE] [rR];
 REPLACE				: [rR] [eE] [pP] [lL] [aA] [cC] [eE];
 RIGHT				: [rR] [iI] [gG] [hH] [tT];
+ROLLUP				: [rR] [oO] [lL] [lL] [uU] [pP];
 ROUND				: [rR] [oO] [uU] [nN] [dD];
 SECOND				: [sS] [eE] [cC] [oO] [nN] [dD];
 SELECT				: [sS] [eE] [lL] [eE] [cC] [tT];

hibernate-core/src/main/antlr/org/hibernate/grammars/hql/HqlParser.g4

@@ -723,6 +723,8 @@ standardFunction
 	|	localTimeFunction
 	|	localDateTimeFunction
 	|	offsetDateTimeFunction
+	|	cube
+	|	rollup
 	;
 
 
@@ -1041,6 +1043,14 @@ positionFunctionStringArgument
 	: expression
 	;
 
+cube
+	: CUBE LEFT_PAREN expression (COMMA expression)* RIGHT_PAREN
+	;
+
+rollup
+	: ROLLUP LEFT_PAREN expression (COMMA expression)* RIGHT_PAREN
+	;
+
 /**
  * The `identifier` is used to provide "keyword as identifier" handling.
  *

hibernate-core/src/main/java/org/hibernate/dialect/Dialect.java

@@ -341,6 +341,10 @@ public abstract class Dialect implements ConversionContext {
 
 		CommonFunctionFactory.aggregates(queryEngine);
 
+		//grouping functions cube() and rollup() supported on some databases
+
+		CommonFunctionFactory.groupings(queryEngine);
+
 		//the ANSI SQL-defined aggregate functions any() and every() are only
 		//supported on one database, but can be emulated using sum() and case,
 		//though there is a more natural mapping on some databases

hibernate-core/src/main/java/org/hibernate/dialect/function/CommonFunctionFactory.java

@@ -1419,6 +1419,15 @@ public class CommonFunctionFactory {
 				.register();
 	}
 
+	public static void groupings(QueryEngine queryEngine) {
+		queryEngine.getSqmFunctionRegistry().namedDescriptorBuilder("cube")
+				.setMinArgumentCount(1)
+				.register();
+		queryEngine.getSqmFunctionRegistry().namedDescriptorBuilder("rollup")
+				.setMinArgumentCount(1)
+				.register();
+	}
+
 	public static void aggregates(QueryEngine queryEngine) {
 		queryEngine.getSqmFunctionRegistry().namedDescriptorBuilder("max")
 				.setExactArgumentCount(1)

hibernate-core/src/main/java/org/hibernate/query/hql/internal/SemanticQueryBuilder.java

@@ -3002,6 +3002,36 @@ public class SemanticQueryBuilder extends HqlParserBaseVisitor implements SqmCre
 		);
 	}
 
+	@Override
+	public SqmExpression visitCube(HqlParser.CubeContext ctx) {
+		List<SqmTypedNode<?>> args = new ArrayList<>();
+		for ( HqlParser.ExpressionContext arg: ctx.expression() ) {
+			args.add( (SqmExpression) arg.accept( this ) );
+		}
+		//ignore DISTINCT
+		return getFunctionDescriptor("cube").generateSqmExpression(
+				args,
+				resolveExpressableTypeBasic( Integer.class ),
+				creationContext.getQueryEngine(),
+				creationContext.getJpaMetamodel().getTypeConfiguration()
+		);
+	}
+
+	@Override
+	public SqmExpression visitRollup(HqlParser.RollupContext ctx) {
+		List<SqmTypedNode<?>> args = new ArrayList<>();
+		for ( HqlParser.ExpressionContext arg: ctx.expression() ) {
+			args.add( (SqmExpression) arg.accept( this ) );
+		}
+		//ignore DISTINCT
+		return getFunctionDescriptor("rollup").generateSqmExpression(
+				args,
+				resolveExpressableTypeBasic( Integer.class ),
+				creationContext.getQueryEngine(),
+				creationContext.getJpaMetamodel().getTypeConfiguration()
+		);
+	}
+
 	@Override
 	public SqmExpression visitSubstringFunction(HqlParser.SubstringFunctionContext ctx) {
 		final SqmExpression source = (SqmExpression) ctx.expression().accept( this );

hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/FunctionTests.java

@@ -954,4 +954,18 @@ public class FunctionTests extends SessionFactoryBasedFunctionalTest {
 		);
 	}
 
+	@Test
+	public void testGroupingFunctions() {
+		inTransaction(
+				session -> {
+					session.createQuery("select max(e.theDouble), e.gender, e.theInt from EntityOfBasics e group by e.gender, e.theInt")
+							.list();
+					session.createQuery("select avg(e.theDouble), e.gender, e.theInt from EntityOfBasics e group by rollup(e.gender, e.theInt)")
+							.list();
+					session.createQuery("select sum(e.theDouble), e.gender, e.theInt from EntityOfBasics e group by cube(e.gender, e.theInt)")
+							.list();
+				}
+		);
+	}
+
 }