diff --git a/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/CockroachLegacyDialect.java b/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/CockroachLegacyDialect.java
index 27919427a0..81ec897ce9 100644
--- a/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/CockroachLegacyDialect.java
+++ b/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/CockroachLegacyDialect.java
@@ -512,8 +512,9 @@ public class CockroachLegacyDialect extends Dialect {
 		functionFactory.jsonRemove_cockroachdb();
 		functionFactory.jsonReplace_postgresql();
 		functionFactory.jsonInsert_postgresql();
-		functionFactory.jsonMergepatch_postgresql();
-		functionFactory.jsonArrayAppend_postgresql();
+		// No support for WITH clause in subquery: https://github.com/cockroachdb/cockroach/issues/131011
+//		functionFactory.jsonMergepatch_postgresql();
+		functionFactory.jsonArrayAppend_postgresql( false );
 		functionFactory.jsonArrayInsert_postgresql();
 
 		// Postgres uses # instead of ^ for XOR
diff --git a/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/PostgreSQLLegacyDialect.java b/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/PostgreSQLLegacyDialect.java
index 291300bab7..6dc5e338ff 100644
--- a/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/PostgreSQLLegacyDialect.java
+++ b/hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/PostgreSQLLegacyDialect.java
@@ -662,8 +662,11 @@ public class PostgreSQLLegacyDialect extends Dialect {
 		functionFactory.jsonRemove_postgresql();
 		functionFactory.jsonReplace_postgresql();
 		functionFactory.jsonInsert_postgresql();
-		functionFactory.jsonMergepatch_postgresql();
-		functionFactory.jsonArrayAppend_postgresql();
+		if ( getVersion().isSameOrAfter( 13 ) ) {
+			// Requires support for WITH clause in subquery which only 13+ provides
+			functionFactory.jsonMergepatch_postgresql();
+		}
+		functionFactory.jsonArrayAppend_postgresql( getVersion().isSameOrAfter( 13 ) );
 		functionFactory.jsonArrayInsert_postgresql();
 
 		if ( getVersion().isSameOrAfter( 9, 4 ) ) {
diff --git a/hibernate-core/src/main/java/org/hibernate/dialect/CockroachDialect.java b/hibernate-core/src/main/java/org/hibernate/dialect/CockroachDialect.java
index 93bc7b5eb0..5e7dee6227 100644
--- a/hibernate-core/src/main/java/org/hibernate/dialect/CockroachDialect.java
+++ b/hibernate-core/src/main/java/org/hibernate/dialect/CockroachDialect.java
@@ -479,8 +479,9 @@ public class CockroachDialect extends Dialect {
 		functionFactory.jsonRemove_cockroachdb();
 		functionFactory.jsonReplace_postgresql();
 		functionFactory.jsonInsert_postgresql();
-		functionFactory.jsonMergepatch_postgresql();
-		functionFactory.jsonArrayAppend_postgresql();
+		// No support for WITH clause in subquery: https://github.com/cockroachdb/cockroach/issues/131011
+//		functionFactory.jsonMergepatch_postgresql();
+		functionFactory.jsonArrayAppend_postgresql( false );
 		functionFactory.jsonArrayInsert_postgresql();
 
 		// Postgres uses # instead of ^ for XOR
diff --git a/hibernate-core/src/main/java/org/hibernate/dialect/PostgreSQLDialect.java b/hibernate-core/src/main/java/org/hibernate/dialect/PostgreSQLDialect.java
index 17b7d0b562..e7900ad373 100644
--- a/hibernate-core/src/main/java/org/hibernate/dialect/PostgreSQLDialect.java
+++ b/hibernate-core/src/main/java/org/hibernate/dialect/PostgreSQLDialect.java
@@ -623,8 +623,11 @@ public class PostgreSQLDialect extends Dialect {
 		functionFactory.jsonRemove_postgresql();
 		functionFactory.jsonReplace_postgresql();
 		functionFactory.jsonInsert_postgresql();
-		functionFactory.jsonMergepatch_postgresql();
-		functionFactory.jsonArrayAppend_postgresql();
+		if ( getVersion().isSameOrAfter( 13 ) ) {
+			// Requires support for WITH clause in subquery which only 13+ provides
+			functionFactory.jsonMergepatch_postgresql();
+		}
+		functionFactory.jsonArrayAppend_postgresql( getVersion().isSameOrAfter( 13 ) );
 		functionFactory.jsonArrayInsert_postgresql();
 
 		functionFactory.makeDateTimeTimestamp();
diff --git a/hibernate-core/src/main/java/org/hibernate/dialect/function/CommonFunctionFactory.java b/hibernate-core/src/main/java/org/hibernate/dialect/function/CommonFunctionFactory.java
index a3d2e63062..8de8aeadf9 100644
--- a/hibernate-core/src/main/java/org/hibernate/dialect/function/CommonFunctionFactory.java
+++ b/hibernate-core/src/main/java/org/hibernate/dialect/function/CommonFunctionFactory.java
@@ -4018,8 +4018,8 @@ public class CommonFunctionFactory {
 	/**
 	 * PostgreSQL json_array_append() function
 	 */
-	public void jsonArrayAppend_postgresql() {
-		functionRegistry.register( "json_array_append", new PostgreSQLJsonArrayAppendFunction( typeConfiguration ) );
+	public void jsonArrayAppend_postgresql(boolean supportsLax) {
+		functionRegistry.register( "json_array_append", new PostgreSQLJsonArrayAppendFunction( supportsLax, typeConfiguration ) );
 	}
 
 	/**
diff --git a/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonArrayAppendFunction.java b/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonArrayAppendFunction.java
index 2c158745c0..a37038fe69 100644
--- a/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonArrayAppendFunction.java
+++ b/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonArrayAppendFunction.java
@@ -21,8 +21,11 @@ import org.hibernate.type.spi.TypeConfiguration;
  */
 public class PostgreSQLJsonArrayAppendFunction extends AbstractJsonArrayAppendFunction {
 
-	public PostgreSQLJsonArrayAppendFunction(TypeConfiguration typeConfiguration) {
+	private final boolean supportsLax;
+
+	public PostgreSQLJsonArrayAppendFunction(boolean supportsLax, TypeConfiguration typeConfiguration) {
 		super( typeConfiguration );
+		this.supportsLax = supportsLax;
 	}
 
 	@Override
@@ -34,7 +37,14 @@ public class PostgreSQLJsonArrayAppendFunction extends AbstractJsonArrayAppendFu
 		final Expression json = (Expression) arguments.get( 0 );
 		final Expression jsonPath = (Expression) arguments.get( 1 );
 		final SqlAstNode value = arguments.get( 2 );
-		sqlAppender.appendSql( "(select jsonb_set_lax(t.d,t.p,(t.d)#>t.p||" );
+		sqlAppender.appendSql( "(select " );
+		if ( supportsLax ) {
+			sqlAppender.appendSql( "jsonb_set_lax" );
+		}
+		else {
+			sqlAppender.appendSql( "case when t.d#>t.p is not null then jsonb_set" );
+		}
+		sqlAppender.appendSql( "(t.d,t.p,(t.d)#>t.p||" );
 		if ( value instanceof Literal && ( (Literal) value ).getLiteralValue() == null ) {
 			sqlAppender.appendSql( "null::jsonb" );
 		}
@@ -47,7 +57,14 @@ public class PostgreSQLJsonArrayAppendFunction extends AbstractJsonArrayAppendFu
 			}
 			sqlAppender.appendSql( ')' );
 		}
-		sqlAppender.appendSql( ",false,'return_target') from (values(" );
+		sqlAppender.appendSql( ",false" );
+		if ( supportsLax ) {
+			sqlAppender.appendSql( ",'return_target')" );
+		}
+		else {
+			sqlAppender.appendSql( ") else t.d end" );
+		}
+		sqlAppender.appendSql( " from (values(" );
 		final boolean needsCast = !isJsonType( json );
 		if ( needsCast ) {
 			sqlAppender.appendSql( "cast(" );
diff --git a/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonRemoveFunction.java b/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonRemoveFunction.java
index b8838771e3..9bb175d5e6 100644
--- a/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonRemoveFunction.java
+++ b/hibernate-core/src/main/java/org/hibernate/dialect/function/json/PostgreSQLJsonRemoveFunction.java
@@ -33,7 +33,6 @@ public class PostgreSQLJsonRemoveFunction extends AbstractJsonRemoveFunction {
 			SqlAstTranslator<?> translator) {
 		final Expression json = (Expression) arguments.get( 0 );
 		final Expression jsonPath = (Expression) arguments.get( 1 );
-		sqlAppender.appendSql( "jsonb_set_lax(" );
 		final boolean needsCast = !isJsonType( json ) && json instanceof JdbcParameter;
 		if ( needsCast ) {
 			sqlAppender.appendSql( "cast(" );
@@ -42,7 +41,7 @@ public class PostgreSQLJsonRemoveFunction extends AbstractJsonRemoveFunction {
 		if ( needsCast ) {
 			sqlAppender.appendSql( " as jsonb)" );
 		}
-		sqlAppender.appendSql( ',' );
+		sqlAppender.appendSql( "#-" );
 		List<JsonPathHelper.JsonPathElement> jsonPathElements =
 				JsonPathHelper.parseJsonPathElements( translator.getLiteralValue( jsonPath ) );
 		sqlAppender.appendSql( "array" );
@@ -63,7 +62,7 @@ public class PostgreSQLJsonRemoveFunction extends AbstractJsonRemoveFunction {
 			}
 			separator = ',';
 		}
-		sqlAppender.appendSql( "]::text[],null,true,'delete_key')" );
+		sqlAppender.appendSql( "]::text[]" );
 	}
 
 	private boolean isJsonType(Expression expression) {