HHH-18497 Add xmlquery function

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

@@ -2176,6 +2176,7 @@ it is necessary to enable the `hibernate.query.hql.xml_functions_enabled` config
 | `xmlforest()` | Constructs an XML forest from the arguments
 | `xmlconcat()` | Concatenates multiple XML fragments to each other
 | `xmlpi()` | Constructs an XML processing instruction
+| `xmlquery()` | Extracts content from XML document using XQuery or XPath
 |===
 
 
@@ -2300,6 +2301,30 @@ include::{xml-example-dir-hql}/XmlPiTest.java[tags=hql-xmlpi-content-example]
 
 WARNING: SAP HANA, MySQL, MariaDB and HSQLDB do not support this function.
 
+[[hql-xmlquery-function]]
+===== `xmlquery()`
+
+Extracts content from an XML document using XQuery or XPath.
+
+[[hql-xmlquery-bnf]]
+[source, antlrv4, indent=0]
+----
+include::{extrasdir}/xmlquery_bnf.txt[]
+----
+
+The first argument represents the XQuery or XPath expression.
+The second argument after the `passing` keyword represents the XML document.
+
+[[hql-xmlquery-example]]
+====
+[source, java, indent=0]
+----
+include::{xml-example-dir-hql}/XmlQueryTest.java[tags=hql-xmlquery-example]
+----
+====
+
+WARNING: SAP HANA, MySQL, MariaDB and HSQLDB do not support this function.
+
 [[hql-user-defined-functions]]
 ==== Native and user-defined functions
 

documentation/src/main/asciidoc/userguide/chapters/query/hql/extras/xmlquery_bnf.txt

@@ -0,0 +1 @@
+"xmlquery(" expression "passing" expression ")"

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

@@ -446,6 +446,7 @@ public class DB2LegacyDialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_db2();
 	}
 
 	@Override

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

@@ -331,6 +331,7 @@ public class OracleLegacyDialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_oracle();
 	}
 
 	@Override

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

@@ -674,6 +674,7 @@ public class PostgreSQLLegacyDialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_postgresql();
 
 		if ( getVersion().isSameOrAfter( 9, 4 ) ) {
 			functionFactory.makeDateTimeTimestamp();

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

@@ -418,6 +418,7 @@ public class SQLServerLegacyDialect extends AbstractTransactSQLDialect {
 		functionFactory.xmlforest_sqlserver();
 		functionFactory.xmlconcat_sqlserver();
 		functionFactory.xmlpi_sqlserver();
+		functionFactory.xmlquery_sqlserver();
 		if ( getVersion().isSameOrAfter( 14 ) ) {
 			functionFactory.listagg_stringAggWithinGroup( "varchar(max)" );
 			functionFactory.jsonArrayAgg_sqlserver( getVersion().isSameOrAfter( 16 ) );

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

@@ -334,6 +334,7 @@ XMLATTRIBUTES		: [xX] [mM] [lL] [aA] [tT] [tT] [rR] [iI] [bB] [uU] [tT] [eE] [sS
 XMLELEMENT			: [xX] [mM] [lL] [eE] [lL] [eE] [mM] [eE] [nN] [tT];
 XMLFOREST			: [xX] [mM] [lL] [fF] [oO] [rR] [eE] [sS] [tT];
 XMLPI				: [xX] [mM] [lL] [pP] [iI];
+XMLQUERY			: [xX] [mM] [lL] [qQ] [uU] [eE] [rR] [yY];
 YEAR				: [yY] [eE] [aA] [rR];
 ZONED				: [zZ] [oO] [nN] [eE] [dD];
 

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

@@ -1721,6 +1721,7 @@ xmlFunction
 	: xmlelementFunction
 	| xmlforestFunction
 	| xmlpiFunction
+	| xmlqueryFunction
 	;
 
 /**
@@ -1751,6 +1752,13 @@ xmlpiFunction
 	: XMLPI LEFT_PAREN NAME identifier (COMMA expression)? RIGHT_PAREN
 	;
 
+/**
+ * The 'xmlquery()' function
+ */
+xmlqueryFunction
+	: XMLQUERY LEFT_PAREN expression PASSING expression RIGHT_PAREN
+	;
+
 /**
  * Support for "soft" keywords which may be used as identifiers
  *
@@ -1961,6 +1969,7 @@ xmlpiFunction
 	| XMLELEMENT
 	| XMLFOREST
 	| XMLPI
+	| XMLQUERY
 	| YEAR
 	| ZONED) {
 		logUseOfReservedWordAsIdentifier( getCurrentToken() );

hibernate-core/src/main/java/org/hibernate/dialect/DB2Dialect.java

@@ -431,6 +431,7 @@ public class DB2Dialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_db2();
 	}
 
 	@Override

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

@@ -421,6 +421,7 @@ public class OracleDialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_oracle();
 	}
 
 	@Override

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

@@ -635,6 +635,7 @@ public class PostgreSQLDialect extends Dialect {
 		functionFactory.xmlforest();
 		functionFactory.xmlconcat();
 		functionFactory.xmlpi();
+		functionFactory.xmlquery_postgresql();
 
 		functionFactory.makeDateTimeTimestamp();
 		// Note that PostgreSQL doesn't support the OVER clause for ordered set-aggregate functions

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

@@ -436,6 +436,7 @@ public class SQLServerDialect extends AbstractTransactSQLDialect {
 		functionFactory.xmlforest_sqlserver();
 		functionFactory.xmlconcat_sqlserver();
 		functionFactory.xmlpi_sqlserver();
+		functionFactory.xmlquery_sqlserver();
 		if ( getVersion().isSameOrAfter( 14 ) ) {
 			functionFactory.listagg_stringAggWithinGroup( "varchar(max)" );
 			functionFactory.jsonArrayAgg_sqlserver( getVersion().isSameOrAfter( 16 ) );

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

@@ -157,14 +157,17 @@ import org.hibernate.dialect.function.xml.H2XmlConcatFunction;
 import org.hibernate.dialect.function.xml.H2XmlElementFunction;
 import org.hibernate.dialect.function.xml.H2XmlForestFunction;
 import org.hibernate.dialect.function.xml.H2XmlPiFunction;
+import org.hibernate.dialect.function.xml.PostgreSQLXmlQueryFunction;
 import org.hibernate.dialect.function.xml.SQLServerXmlConcatFunction;
 import org.hibernate.dialect.function.xml.SQLServerXmlElementFunction;
 import org.hibernate.dialect.function.xml.SQLServerXmlForestFunction;
 import org.hibernate.dialect.function.xml.SQLServerXmlPiFunction;
+import org.hibernate.dialect.function.xml.SQLServerXmlQueryFunction;
 import org.hibernate.dialect.function.xml.XmlConcatFunction;
 import org.hibernate.dialect.function.xml.XmlElementFunction;
 import org.hibernate.dialect.function.xml.XmlForestFunction;
 import org.hibernate.dialect.function.xml.XmlPiFunction;
+import org.hibernate.dialect.function.xml.XmlQueryFunction;
 import org.hibernate.query.sqm.function.SqmFunctionRegistry;
 import org.hibernate.query.sqm.produce.function.ArgumentTypesValidator;
 import org.hibernate.query.sqm.produce.function.FunctionParameterType;
@@ -4215,4 +4218,32 @@ public class CommonFunctionFactory {
 	public void xmlpi_sqlserver() {
 		functionRegistry.register( "xmlpi", new SQLServerXmlPiFunction( typeConfiguration ) );
 	}
+
+	/**
+	 * Oracle xmlquery() function
+	 */
+	public void xmlquery_oracle() {
+		functionRegistry.register( "xmlquery", new XmlQueryFunction( true, typeConfiguration ) );
+	}
+
+	/**
+	 * DB2 xmlquery() function
+	 */
+	public void xmlquery_db2() {
+		functionRegistry.register( "xmlquery", new XmlQueryFunction( false, typeConfiguration ) );
+	}
+
+	/**
+	 * PostgreSQL xmlquery() function
+	 */
+	public void xmlquery_postgresql() {
+		functionRegistry.register( "xmlquery", new PostgreSQLXmlQueryFunction( typeConfiguration ) );
+	}
+
+	/**
+	 * SQL Server xmlquery() function
+	 */
+	public void xmlquery_sqlserver() {
+		functionRegistry.register( "xmlquery", new SQLServerXmlQueryFunction( typeConfiguration ) );
+	}
 }

hibernate-core/src/main/java/org/hibernate/dialect/function/json/ExpressionTypeHelper.java

@@ -35,6 +35,13 @@ public class ExpressionTypeHelper {
 				&& expressionType.getSingleJdbcMapping().getJdbcType().isJson();
 	}
 
+	public static boolean isXml(SqlAstNode node) {
+		final Expression expression = (Expression) node;
+		final JdbcMappingContainer expressionType = expression.getExpressionType();
+		return expressionType.getJdbcTypeCount() == 1
+				&& expressionType.getSingleJdbcMapping().getJdbcType().isXml();
+	}
+
 	public static JdbcType getSingleJdbcType(SqlAstNode node) {
 		final Expression expression = (Expression) node;
 		final JdbcMappingContainer expressionType = expression.getExpressionType();

hibernate-core/src/main/java/org/hibernate/dialect/function/xml/PostgreSQLXmlQueryFunction.java

@@ -0,0 +1,46 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.dialect.function.xml;
+
+import java.util.List;
+
+import org.hibernate.dialect.function.json.ExpressionTypeHelper;
+import org.hibernate.query.ReturnableType;
+import org.hibernate.sql.ast.SqlAstTranslator;
+import org.hibernate.sql.ast.spi.SqlAppender;
+import org.hibernate.sql.ast.tree.SqlAstNode;
+import org.hibernate.sql.ast.tree.expression.Expression;
+import org.hibernate.type.spi.TypeConfiguration;
+
+/**
+ * PostgreSQL xmlquery function.
+ */
+public class PostgreSQLXmlQueryFunction extends XmlQueryFunction {
+
+	public PostgreSQLXmlQueryFunction(TypeConfiguration typeConfiguration) {
+		super( false, typeConfiguration );
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> sqlAstArguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> walker) {
+		final Expression xmlDocument = (Expression) sqlAstArguments.get( 1 );
+		final boolean needsCast = !ExpressionTypeHelper.isXml( xmlDocument );
+		sqlAppender.appendSql( "(select xmlagg(v) from unnest(xpath(" );
+		sqlAstArguments.get( 0 ).accept( walker );
+		sqlAppender.appendSql( ',' );
+		if ( needsCast ) {
+			sqlAppender.appendSql( "cast(" );
+		}
+		sqlAstArguments.get( 1 ).accept( walker );
+		if ( needsCast ) {
+			sqlAppender.appendSql( " as xml)" );
+		}
+		sqlAppender.appendSql( ")) t(v))" );
+	}
+}

hibernate-core/src/main/java/org/hibernate/dialect/function/xml/SQLServerXmlQueryFunction.java

@@ -0,0 +1,45 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.dialect.function.xml;
+
+import java.util.List;
+
+import org.hibernate.dialect.function.json.ExpressionTypeHelper;
+import org.hibernate.query.ReturnableType;
+import org.hibernate.sql.ast.SqlAstTranslator;
+import org.hibernate.sql.ast.spi.SqlAppender;
+import org.hibernate.sql.ast.tree.SqlAstNode;
+import org.hibernate.sql.ast.tree.expression.Expression;
+import org.hibernate.type.spi.TypeConfiguration;
+
+/**
+ * SQL Server xmlquery function.
+ */
+public class SQLServerXmlQueryFunction extends XmlQueryFunction {
+
+	public SQLServerXmlQueryFunction(TypeConfiguration typeConfiguration) {
+		super( false, typeConfiguration );
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> sqlAstArguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> walker) {
+		final Expression xmlDocument = (Expression) sqlAstArguments.get( 1 );
+		final boolean needsCast = !ExpressionTypeHelper.isXml( xmlDocument );
+		if ( needsCast ) {
+			sqlAppender.appendSql( "cast(" );
+		}
+		sqlAstArguments.get( 1 ).accept( walker );
+		if ( needsCast ) {
+			sqlAppender.appendSql( " as xml)" );
+		}
+		sqlAppender.appendSql( ".query(" );
+		sqlAstArguments.get( 0 ).accept( walker );
+		sqlAppender.appendSql( ')' );
+	}
+}

hibernate-core/src/main/java/org/hibernate/dialect/function/xml/XmlQueryFunction.java

@@ -0,0 +1,73 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.dialect.function.xml;
+
+import java.util.List;
+
+import org.hibernate.dialect.function.json.ExpressionTypeHelper;
+import org.hibernate.query.ReturnableType;
+import org.hibernate.query.sqm.function.AbstractSqmSelfRenderingFunctionDescriptor;
+import org.hibernate.query.sqm.function.FunctionKind;
+import org.hibernate.query.sqm.produce.function.ArgumentTypesValidator;
+import org.hibernate.query.sqm.produce.function.StandardArgumentsValidators;
+import org.hibernate.query.sqm.produce.function.StandardFunctionArgumentTypeResolvers;
+import org.hibernate.query.sqm.produce.function.StandardFunctionReturnTypeResolvers;
+import org.hibernate.sql.ast.SqlAstTranslator;
+import org.hibernate.sql.ast.spi.SqlAppender;
+import org.hibernate.sql.ast.tree.SqlAstNode;
+import org.hibernate.sql.ast.tree.expression.Expression;
+import org.hibernate.type.SqlTypes;
+import org.hibernate.type.spi.TypeConfiguration;
+
+import static org.hibernate.query.sqm.produce.function.FunctionParameterType.IMPLICIT_XML;
+import static org.hibernate.query.sqm.produce.function.FunctionParameterType.STRING;
+import static org.hibernate.query.sqm.produce.function.FunctionParameterType.XML;
+
+/**
+ * Standard xmlquery function.
+ */
+public class XmlQueryFunction extends AbstractSqmSelfRenderingFunctionDescriptor {
+
+	private final boolean returningContent;
+
+	public XmlQueryFunction(boolean returningContent, TypeConfiguration typeConfiguration) {
+		super(
+				"xmlquery",
+				FunctionKind.NORMAL,
+				StandardArgumentsValidators.composite(
+						new ArgumentTypesValidator( null, STRING, IMPLICIT_XML )
+				),
+				StandardFunctionReturnTypeResolvers.invariant(
+						typeConfiguration.getBasicTypeRegistry().resolve( String.class, SqlTypes.SQLXML )
+				),
+				StandardFunctionArgumentTypeResolvers.invariant( typeConfiguration, STRING, XML )
+		);
+		this.returningContent = returningContent;
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> sqlAstArguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> walker) {
+		final Expression xmlDocument = (Expression) sqlAstArguments.get( 1 );
+		final boolean needsCast = !ExpressionTypeHelper.isXml( xmlDocument );
+		sqlAppender.appendSql( "xmlquery(" );
+		sqlAstArguments.get( 0 ).accept( walker );
+		sqlAppender.appendSql( " passing " );
+		if ( needsCast ) {
+			sqlAppender.appendSql( "xmlparse(document " );
+		}
+		sqlAstArguments.get( 1 ).accept( walker );
+		if ( needsCast ) {
+			sqlAppender.appendSql( ')' );
+		}
+		if ( returningContent ) {
+			sqlAppender.appendSql( " returning content" );
+		}
+		sqlAppender.appendSql( ')' );
+	}
+}

hibernate-core/src/main/java/org/hibernate/query/criteria/HibernateCriteriaBuilder.java

@@ -4113,6 +4113,22 @@ public interface HibernateCriteriaBuilder extends CriteriaBuilder {
 	@Incubating
 	JpaExpression<String> xmlpi(String elementName, Expression<String> content);
 
+	/**
+	 * Queries the given XML document with the given XPath or XQuery query.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> xmlquery(String query, Expression<?> xmlDocument);
+
+	/**
+	 * Queries the given XML document with the given XPath or XQuery query.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> xmlquery(Expression<String> query, Expression<?> xmlDocument);
+
 	/**
 	 * Creates a named expression. The name is important for the result of the expression,
 	 * e.g. when building an {@code xmlforest}, the name acts as the XML element name.

hibernate-core/src/main/java/org/hibernate/query/criteria/spi/HibernateCriteriaBuilderDelegate.java

@@ -3681,6 +3681,18 @@ public class HibernateCriteriaBuilderDelegate implements HibernateCriteriaBuilde
 		return criteriaBuilder.xmlpi( elementName, content );
 	}
 
+	@Override
+	@Incubating
+	public JpaExpression<String> xmlquery(String query, Expression<?> xmlDocument) {
+		return criteriaBuilder.xmlquery( query, xmlDocument );
+	}
+
+	@Override
+	@Incubating
+	public JpaExpression<String> xmlquery(Expression<String> query, Expression<?> xmlDocument) {
+		return criteriaBuilder.xmlquery( query, xmlDocument );
+	}
+
 	@Override
 	@Incubating
 	public <T> JpaExpression<T> named(Expression<T> expression, String name) {

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

@@ -3043,6 +3043,14 @@ public class SemanticQueryBuilder<R> extends HqlParserBaseVisitor<Object> implem
 				: creationContext.getNodeBuilder().xmlpi( name, (Expression<String>) exprCtx.accept( this ) );
 	}
 
+	@Override
+	public SqmExpression<?> visitXmlqueryFunction(HqlParser.XmlqueryFunctionContext ctx) {
+		checkXmlFunctionsEnabled( ctx );
+		final SqmExpression<String> query = (SqmExpression<String>) ctx.expression( 0 ).accept( this );
+		final SqmExpression<?> xmlDocument = (SqmExpression<?>) ctx.expression( 1 ).accept( this );
+		return creationContext.getNodeBuilder().xmlquery( query, xmlDocument );
+	}
+
 	private void checkXmlFunctionsEnabled(ParserRuleContext ctx) {
 		if ( !creationOptions.isXmlFunctionsEnabled() ) {
 			throw new SemanticException(

hibernate-core/src/main/java/org/hibernate/query/sqm/NodeBuilder.java

@@ -777,6 +777,12 @@ public interface NodeBuilder extends HibernateCriteriaBuilder, BindingContext {
 	@Override
 	SqmExpression<String> xmlpi(String elementName, Expression<String> content);
 
+	@Override
+	SqmExpression<String> xmlquery(String query, Expression<?> xmlDocument);
+
+	@Override
+	SqmExpression<String> xmlquery(Expression<String> query, Expression<?> xmlDocument);
+
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 	// Covariant overrides
 

hibernate-core/src/main/java/org/hibernate/query/sqm/internal/SqmCriteriaNodeBuilder.java

@@ -5764,4 +5764,18 @@ public class SqmCriteriaNodeBuilder implements NodeBuilder, Serializable {
 				queryEngine
 		);
 	}
+
+	@Override
+	public SqmExpression<String> xmlquery(String query, Expression<?> xmlDocument) {
+		return xmlquery( value( query ), xmlDocument );
+	}
+
+	@Override
+	public SqmExpression<String> xmlquery(Expression<String> query, Expression<?> xmlDocument) {
+		return getFunctionDescriptor( "xmlquery" ).generateSqmExpression(
+				asList( (SqmTypedNode<?>) query, (SqmTypedNode<?>) xmlDocument ),
+				null,
+				queryEngine
+		);
+	}
 }

hibernate-core/src/test/java/org/hibernate/orm/test/function/xml/XmlQueryTest.java

@@ -0,0 +1,36 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.function.xml;
+
+import org.hibernate.cfg.QuerySettings;
+
+import org.hibernate.testing.orm.junit.DialectFeatureChecks;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.RequiresDialectFeature;
+import org.hibernate.testing.orm.junit.ServiceRegistry;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.hibernate.testing.orm.junit.Setting;
+import org.junit.jupiter.api.Test;
+
+/**
+ * @author Christian Beikov
+ */
+@DomainModel
+@SessionFactory
+@ServiceRegistry(settings = @Setting(name = QuerySettings.XML_FUNCTIONS_ENABLED, value = "true"))
+@RequiresDialectFeature( feature = DialectFeatureChecks.SupportsXmlquery.class)
+public class XmlQueryTest {
+
+	@Test
+	public void testSimple(SessionFactoryScope scope) {
+		scope.inSession( em -> {
+			//tag::hql-xmlquery-example[]
+			em.createQuery( "select xmlquery('/a/val' passing '<a><val>asd</val></a>')" ).getResultList();
+			//end::hql-xmlquery-example[]
+		} );
+	}
+
+}

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

@@ -201,6 +201,20 @@ public class XmlFunctionTests {
 		);
 	}
 
+	@Test
+	@RequiresDialectFeature(feature = DialectFeatureChecks.SupportsXmlquery.class)
+	public void testXmlquery(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					Tuple tuple = session.createQuery(
+							"select xmlquery('/a/val' passing '<a><val>asd</val></a>')",
+							Tuple.class
+					).getSingleResult();
+					assertXmlEquals( "<val>asd</val>", tuple.get( 0, String.class ) );
+				}
+		);
+	}
+
 	private void assertXmlEquals(String expected, String actual) {
 		final Document expectedDoc = parseXml( xmlNormalize( expected ) );
 		final Document actualDoc = parseXml( xmlNormalize( actual ) );

hibernate-testing/src/main/java/org/hibernate/testing/orm/junit/DialectFeatureChecks.java

@@ -868,6 +868,12 @@ abstract public class DialectFeatureChecks {
 		}
 	}
 
+	public static class SupportsXmlquery implements DialectFeatureCheck {
+		public boolean apply(Dialect dialect) {
+			return definesFunction( dialect, "xmlquery" );
+		}
+	}
+
 	public static class IsJtds implements DialectFeatureCheck {
 		public boolean apply(Dialect dialect) {
 			return dialect instanceof SybaseDialect && ( (SybaseDialect) dialect ).getDriverKind() == SybaseDriverKind.JTDS;