hibernate/hibernate-orm · error · QueryException

Can't emulate null on error clause on MySQL

Error message

Can't emulate null on error clause on MySQL

What it means

Error "Can't emulate null on error clause on MySQL" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/dialect/function/json/MySQLJsonTableFunction.java:43

/**
 * MySQL json_table function.
 */
public class MySQLJsonTableFunction extends JsonTableFunction {

	public MySQLJsonTableFunction(TypeConfiguration typeConfiguration) {
		super( typeConfiguration );
	}

	@Override
	protected void renderJsonTable(
			SqlAppender sqlAppender,
			JsonTableArguments arguments,
			AnonymousTupleTableGroupProducer tupleType,
			String tableIdentifierVariable,
			SqlAstTranslator<?> walker) {
		if ( arguments.errorBehavior() == JsonTableErrorBehavior.NULL ) {
			throw new QueryException( "Can't emulate null on error clause on MySQL" );
		}
		sqlAppender.appendSql( "json_table(" );
		arguments.jsonDocument().accept( walker );
		if ( arguments.jsonPath() == null ) {
			sqlAppender.appendSql( ",'$'" );
		}
		else {
			sqlAppender.appendSql( ',' );
			final JsonPathPassingClause passingClause = arguments.passingClause();
			if ( passingClause != null ) {
				JsonPathHelper.appendInlinedJsonPathIncludingPassingClause(
						sqlAppender,
						"",
						arguments.jsonPath(),
						passingClause,
						walker
				);
			}

View on GitHub (pinned to fad1729dce)

Solutions

1. Remove the NULL ON ERROR clause for MySQL.

When it happens

Trigger: Triggered when the application calls a Hibernate dialect feature that the configured database dialect cannot provide: Can't emulate null on error clause on MySQL.

Common situations: Common when running against a database whose dialect lacks this capability, when a mapping or HQL/Criteria query requests unsupported functionality, or when the wrong dialect is configured for the database in use. Error: Can't emulate null on error clause on MySQL.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/4d95ce836188d1d5. Report an issue: GitHub.