在休眠状态下调用mysql函数返回varchar

通过扩展mysqldialect来创建一个类，如下所示

public class MySqlDialectExtended extends MySQLDialect {public MySqlDialectExtended() {    super();    registerFunction("date_add_interval", new SQLFunctionTemplate(Hibernate.DATE, "date_add(?1, INTERVAL ?2 ?3)"));    registerFunction("date_sub_interval", new SQLFunctionTemplate(Hibernate.DATE, "DATE_SUB(?1, INTERVAL ?2 ?3)"));    registerFunction("weekofyear", new StandardSQLFunction("weekofyear", Hibernate.INTEGER));    registerFunction("group_concat", new StandardSQLFunction("group_concat", Hibernate.STRING));}

}

并在查询中像这样使用它

new Query(" >= date_sub_interval(CURRENT_DATE(),1, DAY)");