我是 JDOQL 的新手,但遇到以下问题。我正在尝试获取部门的平均工资,然后选择平均工资高于某个值的部门。
Query averageSalaryByDep = pm.newQuery(Employee.class);
averageSalaryByDep.setResult("department, avg(salary)");
averageSalaryByDep.setGrouping("department");
Query qry = pm.newQuery(Department.class);
qry.setFilter("this.name == dep.name && averageSalary > 10000");
qry.declareVariables("Department dep, double averageSalary");
qry.addSubquery(averageSalaryByDep, "Department dep, double averageSalary", null);
我目前收到的错误消息:
javax.jdo.JDOUserException: Class name averageSalary could not be resolved
at org.datanucleus.api.jdo.NucleusJDOHelper.getJDOExceptionForNucleusException(NucleusJDOHelper.java:636)
at org.datanucleus.api.jdo.JDOQuery.executeInternal(JDOQuery.java:391)
at org.datanucleus.api.jdo.JDOQuery.execute(JDOQuery.java:216)