HHH-18661 Add unnest() set-returning function and enable XML/JSON based array support on more databases

Author: beikov

docker_db.sh

@@ -434,6 +434,8 @@ use master
 go
 create login $SYBASE_USER with password $SYBASE_PASSWORD
 go
+exec sp_configure 'enable xml', 1
+go
 exec sp_dboption $SYBASE_DB, 'abort tran on log full', true
 go
 exec sp_dboption $SYBASE_DB, 'allow nulls by default', true

documentation/src/main/asciidoc/introduction/Entities.adoc

@@ -866,7 +866,7 @@ This annotation is completely optional, and so we don't usually use it.
 ====
 
 On the other hand a reference to an embeddable type is _never_ polymorphic.
-One `@Embeddable` class `F` may inherit a second `@Embeddable` class `E`, but an attribute of type `E` will always refer to an instance of that concrete class `E`, never to an instance of `F`.
+One `@Embeddable` class `F` may inherit a second `@Embeddable` class `T`, but an attribute of type `T` will always refer to an instance of that concrete class `T`, never to an instance of `F`.
 
 Usually, embeddable types are stored in a "flattened" format.
 Their attributes map columns of the table of their parent entity.
@@ -884,15 +884,15 @@ Next we'll discuss a different kind of relationship: a relationship between Java
 
 An _association_ is a relationship between entities.
 We usually classify associations based on their _multiplicity_.
-If `E` and `F` are both entity classes, then:
+If `T` and `F` are both entity classes, then:
 
-- a _one-to-one_ association relates at most one unique instance `E` with at most one unique instance of `F`,
-- a _many-to-one_ association relates zero or more instances of `E` with a unique instance of `F`, and
-- a _many-to-many_ association relates zero or more instances of `E` with zero or more instance of `F`.
+- a _one-to-one_ association relates at most one unique instance `T` with at most one unique instance of `F`,
+- a _many-to-one_ association relates zero or more instances of `T` with a unique instance of `F`, and
+- a _many-to-many_ association relates zero or more instances of `T` with zero or more instance of `F`.
 
 An association between entity classes may be either:
 
-- _unidirectional_, navigable from `E` to `F` but not from `F` to `E`, or
+- _unidirectional_, navigable from `T` to `F` but not from `F` to `T`, or
 - _bidirectional_, and navigable in either direction.
 
 In this example data model, we can see the sorts of associations which are possible:

documentation/src/main/asciidoc/introduction/Generator.adoc

@@ -537,9 +537,9 @@ Optionally, a query method--or a finder method which returns multiple results--m
 | Parameter type | Purpose | Example argument
 
 | `Page` | Specifies a page of query results | Page.first(20)
-| `Order<? super E>` | Specifies an entity attribute to order by, if `E` is the entity type returned by the query | Order.asc(Book_.title)
+| `Order<? super E>` | Specifies an entity attribute to order by, if `T` is the entity type returned by the query | Order.asc(Book_.title)
 | `List<Order? super E>` +
-(or varargs) | Specifies entity attributes to order by, if `E` is the entity type returned by the query | List.of(Order.asc(Book_.title), Order.asc(Book_.isbn))
+(or varargs) | Specifies entity attributes to order by, if `T` is the entity type returned by the query | List.of(Order.asc(Book_.title), Order.asc(Book_.isbn))
 | `Order<Object[]>` | Specifies a column to order by, if the query returns a projection list | Order.asc(1)
 | `List<Object[]>` +
 (or varargs) | Specifies columns to order by, if the query returns a projection list | List.of(Order.asc(1), Order.desc(2))

documentation/src/main/asciidoc/querylanguage/Expressions.adoc

@@ -89,7 +89,7 @@ It's not usually necessary to specify the precision explicitly.
 
 [NOTE]
 ====
-In a literal with an exponent, the `E` is case-insensitive.
+In a literal with an exponent, the `T` is case-insensitive.
 Similarly, the Java-style postfix is case-insensitive.
 ====
 

documentation/src/main/asciidoc/userguide/chapters/query/hql/QueryLanguage.adoc

@@ -458,7 +458,7 @@ It's not usually necessary to specify the precision explicitly.
 
 [NOTE]
 ====
-In a literal with an exponent, the `E` is case-insensitive.
+In a literal with an exponent, the `T` is case-insensitive.
 Similarly, the Java-style postfix is case-insensitive.
 ====
 

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/CockroachLegacyDialect.java

@@ -372,23 +372,23 @@ protected void contributeCockroachTypes(TypeContributions typeContributions, Ser
 				if ( getVersion().isSameOrAfter( 20, 0 ) ) {
 					jdbcTypeRegistry.addDescriptorIfAbsent( PgJdbcHelper.getInetJdbcType( serviceRegistry ) );
 					jdbcTypeRegistry.addDescriptorIfAbsent( PgJdbcHelper.getJsonbJdbcType( serviceRegistry ) );
-					jdbcTypeRegistry.addDescriptorIfAbsent( PgJdbcHelper.getJsonbArrayJdbcType( serviceRegistry ) );
+					jdbcTypeRegistry.addTypeConstructor( PgJdbcHelper.getJsonbArrayJdbcType( serviceRegistry ) );
 				}
 				else {
 					jdbcTypeRegistry.addDescriptorIfAbsent( PgJdbcHelper.getJsonJdbcType( serviceRegistry ) );
-					jdbcTypeRegistry.addDescriptorIfAbsent( PgJdbcHelper.getJsonArrayJdbcType( serviceRegistry ) );
+					jdbcTypeRegistry.addTypeConstructor( PgJdbcHelper.getJsonArrayJdbcType( serviceRegistry ) );
 				}
 			}
 			else {
 				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingIntervalSecondJdbcType.INSTANCE );
 				if ( getVersion().isSameOrAfter( 20, 0 ) ) {
 					jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingInetJdbcType.INSTANCE );
 					jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonJdbcType.JSONB_INSTANCE );
-					jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonArrayJdbcType.JSONB_INSTANCE );
+					jdbcTypeRegistry.addTypeConstructor( PostgreSQLCastingJsonArrayJdbcTypeConstructor.JSONB_INSTANCE );
 				}
 				else {
 					jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonJdbcType.JSON_INSTANCE );
-					jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonArrayJdbcType.JSON_INSTANCE );
+					jdbcTypeRegistry.addTypeConstructor( PostgreSQLCastingJsonArrayJdbcTypeConstructor.JSON_INSTANCE );
 				}
 			}
 		}
@@ -398,11 +398,11 @@ protected void contributeCockroachTypes(TypeContributions typeContributions, Ser
 			if ( getVersion().isSameOrAfter( 20, 0 ) ) {
 				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingInetJdbcType.INSTANCE );
 				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonJdbcType.JSONB_INSTANCE );
-				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonArrayJdbcType.JSONB_INSTANCE );
+				jdbcTypeRegistry.addTypeConstructor( PostgreSQLCastingJsonArrayJdbcTypeConstructor.JSONB_INSTANCE );
 			}
 			else {
 				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonJdbcType.JSON_INSTANCE );
-				jdbcTypeRegistry.addDescriptorIfAbsent( PostgreSQLCastingJsonArrayJdbcType.JSON_INSTANCE );
+				jdbcTypeRegistry.addTypeConstructor( PostgreSQLCastingJsonArrayJdbcTypeConstructor.JSON_INSTANCE );
 			}
 		}
 
@@ -518,6 +518,8 @@ public void initializeFunctionRegistry(FunctionContributions functionContributio
 		functionFactory.jsonArrayAppend_postgresql( false );
 		functionFactory.jsonArrayInsert_postgresql();
 
+		functionFactory.unnest();
+
 		// Postgres uses # instead of ^ for XOR
 		functionContributions.getFunctionRegistry().patternDescriptorBuilder( "bitxor", "(?1#?2)" )
 				.setExactArgumentCount( 2 )

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/DB2LegacyDialect.java

@@ -88,6 +88,7 @@
 import org.hibernate.tool.schema.extract.internal.SequenceInformationExtractorNoOpImpl;
 import org.hibernate.tool.schema.extract.spi.SequenceInformationExtractor;
 import org.hibernate.type.JavaObjectType;
+import org.hibernate.type.SqlTypes;
 import org.hibernate.type.StandardBasicTypes;
 import org.hibernate.type.descriptor.ValueExtractor;
 import org.hibernate.type.descriptor.java.JavaType;
@@ -455,6 +456,14 @@ public void initializeFunctionRegistry(FunctionContributions functionContributio
 			functionFactory.xmlexists_db2_legacy();
 		}
 		functionFactory.xmlagg();
+
+		functionFactory.unnest();
+	}
+
+	@Override
+	public int getPreferredSqlTypeCodeForArray() {
+		// Even if DB2 11 supports JSON functions, it's not possible to unnest a JSON array to rows, so stick to XML
+		return SqlTypes.XML_ARRAY;
 	}
 
 	@Override

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/DB2LegacySqlAstTranslator.java

@@ -28,6 +28,8 @@
 import org.hibernate.sql.ast.tree.expression.Literal;
 import org.hibernate.sql.ast.tree.expression.SqlTuple;
 import org.hibernate.sql.ast.tree.expression.Summarization;
+import org.hibernate.sql.ast.tree.from.DerivedTableReference;
+import org.hibernate.sql.ast.tree.from.FunctionTableReference;
 import org.hibernate.sql.ast.tree.from.NamedTableReference;
 import org.hibernate.sql.ast.tree.from.QueryPartTableReference;
 import org.hibernate.sql.ast.tree.from.TableGroup;
@@ -253,6 +255,17 @@ public void visitQueryPartTableReference(QueryPartTableReference tableReference)
 		inLateral = oldLateral;
 	}
 
+	@Override
+	protected void renderDerivedTableReference(DerivedTableReference tableReference) {
+		if ( tableReference instanceof FunctionTableReference && tableReference.isLateral() ) {
+			// No need for a lateral keyword for functions
+			tableReference.accept( this );
+		}
+		else {
+			super.renderDerivedTableReference( tableReference );
+		}
+	}
+
 	@Override
 	public void visitSelectStatement(SelectStatement statement) {
 		if ( getQueryPartForRowNumbering() == statement.getQueryPart() && inLateral ) {

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/DB2zLegacySqlAstTranslator.java

@@ -4,17 +4,13 @@
  */
 package org.hibernate.community.dialect;
 
-import org.hibernate.LockMode;
 import org.hibernate.dialect.DatabaseVersion;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.query.sqm.ComparisonOperator;
 import org.hibernate.sql.ast.tree.Statement;
 import org.hibernate.sql.ast.tree.expression.Expression;
 import org.hibernate.sql.ast.tree.expression.Literal;
-import org.hibernate.sql.ast.tree.from.FunctionTableReference;
-import org.hibernate.sql.ast.tree.from.NamedTableReference;
-import org.hibernate.sql.ast.tree.from.TableGroup;
-import org.hibernate.sql.ast.tree.from.TableReference;
+import org.hibernate.sql.ast.tree.from.QueryPartTableReference;
 import org.hibernate.sql.ast.tree.select.QueryPart;
 import org.hibernate.sql.exec.spi.JdbcOperation;
 
@@ -58,28 +54,10 @@ protected void renderComparison(Expression lhs, ComparisonOperator operator, Exp
 	}
 
 	@Override
-	protected boolean renderPrimaryTableReference(TableGroup tableGroup, LockMode lockMode) {
-		if ( shouldInlineCte( tableGroup ) ) {
-			inlineCteTableGroup( tableGroup, lockMode );
-			return false;
-		}
-		final TableReference tableReference = tableGroup.getPrimaryTableReference();
-		if ( tableReference instanceof NamedTableReference ) {
-			return renderNamedTableReference( (NamedTableReference) tableReference, lockMode );
-		}
+	public void visitQueryPartTableReference(QueryPartTableReference tableReference) {
 		// DB2 z/OS we need the "table" qualifier for table valued functions or lateral sub-queries
 		append( "table " );
-		tableReference.accept( this );
-		return false;
-	}
-
-	@Override
-	public void visitFunctionTableReference(FunctionTableReference tableReference) {
-		// For the table qualifier we need parenthesis on DB2 z/OS
-		append( OPEN_PARENTHESIS );
-		tableReference.getFunctionExpression().accept( this );
-		append( CLOSE_PARENTHESIS );
-		renderDerivedTableReference( tableReference );
+		super.visitQueryPartTableReference( tableReference );
 	}
 
 	@Override

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/H2LegacyDialect.java

@@ -296,7 +296,7 @@ public void contributeTypes(TypeContributions typeContributions, ServiceRegistry
 		}
 		if ( getVersion().isSameOrAfter( 1, 4, 200 ) ) {
 			jdbcTypeRegistry.addDescriptorIfAbsent( H2JsonJdbcType.INSTANCE );
-			jdbcTypeRegistry.addDescriptorIfAbsent( H2JsonArrayJdbcType.INSTANCE );
+			jdbcTypeRegistry.addTypeConstructor( H2JsonArrayJdbcTypeConstructor.INSTANCE );
 		}
 		jdbcTypeRegistry.addDescriptor( EnumJdbcType.INSTANCE );
 		jdbcTypeRegistry.addDescriptor( OrdinalEnumJdbcType.INSTANCE );
@@ -427,6 +427,10 @@ public void initializeFunctionRegistry(FunctionContributions functionContributio
 		else {
 			functionFactory.listagg_groupConcat();
 		}
+
+		// H2 has a function named "unnest", but it only accepts a scalar
+		// and since H2 has no support for lateral joins, it's completely useless
+//		functionFactory.unnest();
 	}
 
 	/**