HHH-18604 Add json_set function

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

@@ -1639,6 +1639,7 @@ it is necessary to enable the `hibernate.query.hql.json_functions_enabled` confi
 | `json_query()` | Queries non-scalar values by JSON path in a JSON document
 | `json_arrayagg()` | Creates a JSON array by aggregating values
 | `json_objectagg()` | Creates a JSON object by aggregating values
+| `json_set()` | Inserts/Replaces a value by JSON path within a JSON document
 |===
 
 
@@ -2013,6 +2014,22 @@ include::{json-example-dir-hql}/JsonObjectAggregateTest.java[tags=hql-json-objec
 
 WARNING: Some databases like e.g. MySQL, SAP HANA, DB2 and SQL Server do not support raising an error on duplicate keys.
 
+[[hql-json-set-function]]
+===== `json_set()`
+
+Inserts/Replaces a value by JSON path within a JSON document.
+The function takes 3 arguments, the json document, the json path and the new value to set/insert.
+
+[[hql-json-set-example]]
+====
+[source, java, indent=0]
+----
+include::{json-example-dir-hql}/JsonSetTest.java[tags=hql-json-set-example]
+----
+====
+
+WARNING: SAP HANA, DB2, H2 and HSQLDB do not support this function.
+
 [[hql-user-defined-functions]]
 ==== Native and user-defined functions
 

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

@@ -508,6 +508,7 @@ public class CockroachLegacyDialect extends Dialect {
 		functionFactory.jsonArray_postgresql();
 		functionFactory.jsonArrayAgg_postgresql( false );
 		functionFactory.jsonObjectAgg_postgresql( false );
+		functionFactory.jsonSet_postgresql();
 
 		// Postgres uses # instead of ^ for XOR
 		functionContributions.getFunctionRegistry().patternDescriptorBuilder( "bitxor", "(?1#?2)" )

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

@@ -660,6 +660,7 @@ public class MySQLLegacyDialect extends Dialect {
 			functionFactory.jsonArray_mysql();
 			functionFactory.jsonArrayAgg_mysql();
 			functionFactory.jsonObjectAgg_mysql();
+			functionFactory.jsonSet_mysql();
 		}
 	}
 

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

@@ -316,6 +316,7 @@ public class OracleLegacyDialect extends Dialect {
 			functionFactory.jsonObject_oracle();
 			functionFactory.jsonArray_oracle();
 			functionFactory.jsonArrayAgg_oracle();
+			functionFactory.jsonSet_oracle();
 		}
 	}
 

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

@@ -658,6 +658,7 @@ public class PostgreSQLLegacyDialect extends Dialect {
 				functionFactory.jsonObjectAgg_postgresql( false );
 			}
 		}
+		functionFactory.jsonSet_postgresql();
 
 		if ( getVersion().isSameOrAfter( 9, 4 ) ) {
 			functionFactory.makeDateTimeTimestamp();

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

@@ -406,6 +406,7 @@ public class SQLServerLegacyDialect extends AbstractTransactSQLDialect {
 			functionFactory.jsonExists_sqlserver();
 			functionFactory.jsonObject_sqlserver();
 			functionFactory.jsonArray_sqlserver();
+			functionFactory.jsonSet_sqlserver();
 		}
 		if ( getVersion().isSameOrAfter( 14 ) ) {
 			functionFactory.listagg_stringAggWithinGroup( "varchar(max)" );

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

@@ -475,6 +475,7 @@ public class CockroachDialect extends Dialect {
 		functionFactory.jsonArray_postgresql();
 		functionFactory.jsonArrayAgg_postgresql( false );
 		functionFactory.jsonObjectAgg_postgresql( false );
+		functionFactory.jsonSet_postgresql();
 
 		// Postgres uses # instead of ^ for XOR
 		functionContributions.getFunctionRegistry().patternDescriptorBuilder( "bitxor", "(?1#?2)" )

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

@@ -645,6 +645,7 @@ public class MySQLDialect extends Dialect {
 		functionFactory.jsonArray_mysql();
 		functionFactory.jsonArrayAgg_mysql();
 		functionFactory.jsonObjectAgg_mysql();
+		functionFactory.jsonSet_mysql();
 	}
 
 	@Override

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

@@ -407,6 +407,7 @@ public class OracleDialect extends Dialect {
 		functionFactory.jsonObject_oracle();
 		functionFactory.jsonArray_oracle();
 		functionFactory.jsonArrayAgg_oracle();
+		functionFactory.jsonSet_oracle();
 	}
 
 	@Override

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

@@ -619,6 +619,7 @@ public class PostgreSQLDialect extends Dialect {
 				functionFactory.jsonObjectAgg_postgresql( false );
 			}
 		}
+		functionFactory.jsonSet_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

@@ -424,6 +424,7 @@ public class SQLServerDialect extends AbstractTransactSQLDialect {
 			functionFactory.jsonExists_sqlserver();
 			functionFactory.jsonObject_sqlserver();
 			functionFactory.jsonArray_sqlserver();
+			functionFactory.jsonSet_sqlserver();
 		}
 		if ( getVersion().isSameOrAfter( 14 ) ) {
 			functionFactory.listagg_stringAggWithinGroup( "varchar(max)" );

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

@@ -118,12 +118,14 @@ import org.hibernate.dialect.function.json.MySQLJsonValueFunction;
 import org.hibernate.dialect.function.json.OracleJsonArrayAggFunction;
 import org.hibernate.dialect.function.json.OracleJsonArrayFunction;
 import org.hibernate.dialect.function.json.OracleJsonObjectFunction;
+import org.hibernate.dialect.function.json.OracleJsonSetFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonArrayAggFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonArrayFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonExistsFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonObjectAggFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonObjectFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonQueryFunction;
+import org.hibernate.dialect.function.json.PostgreSQLJsonSetFunction;
 import org.hibernate.dialect.function.json.PostgreSQLJsonValueFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonArrayAggFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonArrayFunction;
@@ -131,15 +133,18 @@ import org.hibernate.dialect.function.json.SQLServerJsonExistsFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonObjectAggFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonObjectFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonQueryFunction;
+import org.hibernate.dialect.function.json.SQLServerJsonSetFunction;
 import org.hibernate.dialect.function.json.SQLServerJsonValueFunction;
 import org.hibernate.query.sqm.function.SqmFunctionRegistry;
 import org.hibernate.query.sqm.produce.function.ArgumentTypesValidator;
+import org.hibernate.query.sqm.produce.function.FunctionParameterType;
 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.SqlAstNodeRenderingMode;
 import org.hibernate.type.BasicType;
 import org.hibernate.type.BasicTypeRegistry;
+import org.hibernate.type.SqlTypes;
 import org.hibernate.type.StandardBasicTypes;
 import org.hibernate.type.spi.TypeConfiguration;
 
@@ -3796,4 +3801,42 @@ public class CommonFunctionFactory {
 	public void jsonObjectAgg_db2() {
 		functionRegistry.register( "json_objectagg", new DB2JsonObjectAggFunction( typeConfiguration ) );
 	}
+
+	/**
+	 * PostgreSQL json_set() function
+	 */
+	public void jsonSet_postgresql() {
+		functionRegistry.register( "json_set", new PostgreSQLJsonSetFunction( typeConfiguration ) );
+	}
+
+	/**
+	 * MySQL json_set() function
+	 */
+	public void jsonSet_mysql() {
+		functionRegistry.namedDescriptorBuilder( "json_set" )
+				.setArgumentsValidator( new ArgumentTypesValidator(
+						StandardArgumentsValidators.exactly( 3 ),
+						FunctionParameterType.IMPLICIT_JSON,
+						FunctionParameterType.STRING,
+						FunctionParameterType.ANY
+				) )
+				.setReturnTypeResolver( StandardFunctionReturnTypeResolvers.invariant(
+						typeConfiguration.getBasicTypeRegistry().resolve( String.class, SqlTypes.JSON )
+				) )
+				.register();
+	}
+
+	/**
+	 * Oracle json_set() function
+	 */
+	public void jsonSet_oracle() {
+		functionRegistry.register( "json_set", new OracleJsonSetFunction( typeConfiguration ) );
+	}
+
+	/**
+	 * SQL Server json_set() function
+	 */
+	public void jsonSet_sqlserver() {
+		functionRegistry.register( "json_set", new SQLServerJsonSetFunction( typeConfiguration ) );
+	}
 }

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

@@ -0,0 +1,40 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.dialect.function.json;
+
+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.FunctionParameterType;
+import org.hibernate.query.sqm.produce.function.StandardArgumentsValidators;
+import org.hibernate.query.sqm.produce.function.StandardFunctionReturnTypeResolvers;
+import org.hibernate.type.SqlTypes;
+import org.hibernate.type.spi.TypeConfiguration;
+
+/**
+ * Standard json_set function.
+ */
+public abstract class AbstractJsonSetFunction extends AbstractSqmSelfRenderingFunctionDescriptor {
+
+	public AbstractJsonSetFunction(TypeConfiguration typeConfiguration) {
+		super(
+				"json_set",
+				FunctionKind.NORMAL,
+				new ArgumentTypesValidator(
+						StandardArgumentsValidators.exactly( 3 ),
+						FunctionParameterType.IMPLICIT_JSON,
+						FunctionParameterType.STRING,
+						FunctionParameterType.ANY
+				),
+				StandardFunctionReturnTypeResolvers.invariant(
+						typeConfiguration.getBasicTypeRegistry().resolve( String.class, SqlTypes.JSON )
+				),
+				null
+		);
+	}
+
+}

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

@@ -0,0 +1,44 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.dialect.function.json;
+
+import java.util.List;
+
+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;
+
+/**
+ * Oracle json_set function.
+ */
+public class OracleJsonSetFunction extends AbstractJsonSetFunction {
+
+	public OracleJsonSetFunction(TypeConfiguration typeConfiguration) {
+		super( typeConfiguration );
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> arguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> translator) {
+		final Expression json = (Expression) arguments.get( 0 );
+		final Expression jsonPath = (Expression) arguments.get( 1 );
+		final SqlAstNode value = arguments.get( 2 );
+		sqlAppender.appendSql( "json_transform(" );
+		json.accept( translator );
+		sqlAppender.appendSql( ",set " );
+		jsonPath.accept( translator );
+		sqlAppender.appendSql( '=' );
+		value.accept( translator );
+		sqlAppender.appendSql( ')' );
+	}
+}

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

@@ -0,0 +1,90 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.dialect.function.json;
+
+import java.util.List;
+
+import org.hibernate.QueryException;
+import org.hibernate.metamodel.mapping.JdbcMappingContainer;
+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.sql.ast.tree.expression.JdbcParameter;
+import org.hibernate.sql.ast.tree.expression.Literal;
+import org.hibernate.type.spi.TypeConfiguration;
+
+/**
+ * PostgreSQL json_set function.
+ */
+public class PostgreSQLJsonSetFunction extends AbstractJsonSetFunction {
+
+	public PostgreSQLJsonSetFunction(TypeConfiguration typeConfiguration) {
+		super( typeConfiguration );
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> arguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> translator) {
+		final Expression json = (Expression) arguments.get( 0 );
+		final Expression jsonPath = (Expression) arguments.get( 1 );
+		final SqlAstNode value = arguments.get( 2 );
+		sqlAppender.appendSql( "jsonb_set(" );
+		final boolean needsCast = !isJsonType( json ) && json instanceof JdbcParameter;
+		if ( needsCast ) {
+			sqlAppender.appendSql( "cast(" );
+		}
+		json.accept( translator );
+		if ( needsCast ) {
+			sqlAppender.appendSql( " as jsonb)" );
+		}
+		sqlAppender.appendSql( ',' );
+		List<JsonPathHelper.JsonPathElement> jsonPathElements =
+				JsonPathHelper.parseJsonPathElements( translator.getLiteralValue( jsonPath ) );
+		sqlAppender.appendSql( "array" );
+		char separator = '[';
+		for ( JsonPathHelper.JsonPathElement pathElement : jsonPathElements ) {
+			sqlAppender.appendSql( separator );
+			if ( pathElement instanceof JsonPathHelper.JsonAttribute attribute ) {
+				sqlAppender.appendSingleQuoteEscapedString( attribute.attribute() );
+			}
+			else if ( pathElement instanceof JsonPathHelper.JsonParameterIndexAccess ) {
+				final String parameterName = ( (JsonPathHelper.JsonParameterIndexAccess) pathElement ).parameterName();
+				throw new QueryException( "JSON path [" + jsonPath + "] uses parameter [" + parameterName + "] that is not passed" );
+			}
+			else {
+				sqlAppender.appendSql( '\'' );
+				sqlAppender.appendSql( ( (JsonPathHelper.JsonIndexAccess) pathElement ).index() );
+				sqlAppender.appendSql( '\'' );
+			}
+			separator = ',';
+		}
+		sqlAppender.appendSql( "]::text[]," );
+		if ( value instanceof Literal && ( (Literal) value ).getLiteralValue() == null ) {
+			sqlAppender.appendSql( "null::jsonb" );
+		}
+		else {
+			sqlAppender.appendSql( "to_jsonb(" );
+			value.accept( translator );
+			if ( value instanceof Literal literal && literal.getJdbcMapping().getJdbcType().isString() ) {
+				// PostgreSQL until version 16 is not smart enough to infer the type of a string literal
+				sqlAppender.appendSql( "::text" );
+			}
+			sqlAppender.appendSql( ')' );
+		}
+		sqlAppender.appendSql( ",true)" );
+	}
+
+	private boolean isJsonType(Expression expression) {
+		final JdbcMappingContainer expressionType = expression.getExpressionType();
+		return expressionType != null && expressionType.getSingleJdbcMapping().getJdbcType().isJson();
+	}
+}

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

@@ -0,0 +1,44 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.dialect.function.json;
+
+import java.util.List;
+
+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 json_set function.
+ */
+public class SQLServerJsonSetFunction extends AbstractJsonSetFunction {
+
+	public SQLServerJsonSetFunction(TypeConfiguration typeConfiguration) {
+		super( typeConfiguration );
+	}
+
+	@Override
+	public void render(
+			SqlAppender sqlAppender,
+			List<? extends SqlAstNode> arguments,
+			ReturnableType<?> returnType,
+			SqlAstTranslator<?> translator) {
+		final Expression json = (Expression) arguments.get( 0 );
+		final Expression jsonPath = (Expression) arguments.get( 1 );
+		final SqlAstNode value = arguments.get( 2 );
+		sqlAppender.appendSql( "json_modify(" );
+		json.accept( translator );
+		sqlAppender.appendSql( ',' );
+		jsonPath.accept( translator );
+		sqlAppender.appendSql( ',' );
+		value.accept( translator );
+		sqlAppender.appendSql( ')' );
+	}
+}

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

@@ -3911,6 +3911,38 @@ public interface HibernateCriteriaBuilder extends CriteriaBuilder {
 	@Incubating
 	JpaExpression<String> jsonObjectAggWithUniqueKeysAndNulls(Expression<?> key, Expression<?> value, Predicate filter);
 
+	/**
+	 * Inserts/Replaces a value by JSON path within a JSON document.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Expression<?> value);
+
+	/**
+	 * Inserts/Replaces a value by JSON path within a JSON document.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Expression<?> value);
+
+	/**
+	 * Inserts/Replaces a value by JSON path within a JSON document.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Object value);
+
+	/**
+	 * Inserts/Replaces a value by JSON path within a JSON document.
+	 *
+	 * @since 7.0
+	 */
+	@Incubating
+	JpaExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Object value);
+
 	@Override
 	JpaPredicate and(List<Predicate> restrictions);
 

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

@@ -3523,4 +3523,28 @@ public class HibernateCriteriaBuilderDelegate implements HibernateCriteriaBuilde
 			Predicate filter) {
 		return criteriaBuilder.jsonObjectAggWithUniqueKeysAndNulls( key, value, filter );
 	}
+
+	@Override
+	@Incubating
+	public JpaExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Expression<?> value) {
+		return criteriaBuilder.jsonSet( jsonDocument, jsonPath, value );
+	}
+
+	@Override
+	@Incubating
+	public JpaExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Expression<?> value) {
+		return criteriaBuilder.jsonSet( jsonDocument, jsonPath, value );
+	}
+
+	@Override
+	@Incubating
+	public JpaExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Object value) {
+		return criteriaBuilder.jsonSet( jsonDocument, jsonPath, value );
+	}
+
+	@Override
+	@Incubating
+	public JpaExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Object value) {
+		return criteriaBuilder.jsonSet( jsonDocument, jsonPath, value );
+	}
 }

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

@@ -703,6 +703,18 @@ public interface NodeBuilder extends HibernateCriteriaBuilder, BindingContext {
 	@Override
 	SqmExpression<String> jsonObjectAgg(Expression<?> key, Expression<?> value, Predicate filter);
 
+	@Override
+	SqmExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Object value);
+
+	@Override
+	SqmExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Object value);
+
+	@Override
+	SqmExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Expression<?> value);
+
+	@Override
+	SqmExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Expression<?> value);
+
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 	// Covariant overrides
 

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

@@ -5555,4 +5555,29 @@ public class SqmCriteriaNodeBuilder implements NodeBuilder, Serializable {
 		}
 		return list;
 	}
+
+	@Override
+	public SqmExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Object value) {
+		return jsonSet( jsonDocument, jsonPath, value( value ) );
+	}
+
+	@Override
+	public SqmExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Object value) {
+		return jsonSet( jsonDocument, value( jsonPath ), value( value ) );
+	}
+
+	@Override
+	public SqmExpression<String> jsonSet(Expression<?> jsonDocument, String jsonPath, Expression<?> value) {
+		return jsonSet( jsonDocument, value( jsonPath ), value );
+	}
+
+	@Override
+	public SqmExpression<String> jsonSet(Expression<?> jsonDocument, Expression<String> jsonPath, Expression<?> value) {
+		//noinspection unchecked
+		return getFunctionDescriptor( "json_set" ).generateSqmExpression(
+				(List<? extends SqmTypedNode<?>>) (List<?>) asList( jsonDocument, jsonPath, value ),
+				null,
+				queryEngine
+		);
+	}
 }

hibernate-core/src/test/java/org/hibernate/orm/test/function/json/JsonSetTest.java

@@ -0,0 +1,46 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.orm.test.function.json;
+
+import org.hibernate.cfg.QuerySettings;
+import org.hibernate.dialect.CockroachDialect;
+import org.hibernate.dialect.DB2Dialect;
+import org.hibernate.dialect.HANADialect;
+import org.hibernate.dialect.MySQLDialect;
+import org.hibernate.dialect.PostgreSQLDialect;
+import org.hibernate.dialect.SQLServerDialect;
+
+import org.hibernate.testing.orm.domain.StandardDomainModel;
+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.hibernate.testing.orm.junit.SkipForDialect;
+import org.junit.jupiter.api.Test;
+
+/**
+ * @author Christian Beikov
+ */
+@DomainModel(standardModels = StandardDomainModel.GAMBIT)
+@SessionFactory
+@ServiceRegistry(settings = @Setting(name = QuerySettings.JSON_FUNCTIONS_ENABLED, value = "true"))
+@RequiresDialectFeature( feature = DialectFeatureChecks.SupportsJsonSet.class)
+public class JsonSetTest {
+
+	@Test
+	public void testSimple(SessionFactoryScope scope) {
+		scope.inSession( em -> {
+			//tag::hql-json-set-example[]
+			em.createQuery( "select json_set('{\"a\":1}', '$.a', 2)" ).getResultList();
+			//end::hql-json-set-example[]
+		} );
+	}
+
+}

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

@@ -466,6 +466,38 @@ public class JsonFunctionTests {
 		);
 	}
 
+	@Test
+	@RequiresDialectFeature(feature = DialectFeatureChecks.SupportsJsonSet.class)
+	public void testJsonSet(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					String json = session.createQuery(
+							"select json_set('{}', '$.a', 123)",
+							String.class
+					).getSingleResult();
+					Map<String, Object> object = parseObject( json );
+					assertEquals( 1, object.size() );
+					assertEquals( 123, object.get( "a" ) );
+				}
+		);
+	}
+
+	@Test
+	@RequiresDialectFeature(feature = DialectFeatureChecks.SupportsJsonSet.class)
+	public void testJsonSetReplace(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					String json = session.createQuery(
+							"select json_set('{\"a\":456}', '$.a', 123)",
+							String.class
+					).getSingleResult();
+					Map<String, Object> object = parseObject( json );
+					assertEquals( 1, object.size() );
+					assertEquals( 123, object.get( "a" ) );
+				}
+		);
+	}
+
 	private static final ObjectMapper MAPPER = new ObjectMapper();
 
 	private static Map<String, Object> parseObject(String json) {

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

@@ -793,6 +793,12 @@ abstract public class DialectFeatureChecks {
 		}
 	}
 
+	public static class SupportsJsonSet implements DialectFeatureCheck {
+		public boolean apply(Dialect dialect) {
+			return definesFunction( dialect, "json_set" );
+		}
+	}
+
 	public static class IsJtds implements DialectFeatureCheck {
 		public boolean apply(Dialect dialect) {
 			return dialect instanceof SybaseDialect && ( (SybaseDialect) dialect ).getDriverKind() == SybaseDriverKind.JTDS;