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实现方式 ：
1. 注入em:
@PersistenceContextprivate EntityManager entityManager;注入方式 2：
@PersistenceUnitprivate EntityManagerFactory emf;
2. 得到em：
private EntityManager getEm() {return this.entityManager;}对应第2种注入方式：
/*** 得EntityManager** @return*/private EntityManager getEm() {return emf.createEntityManager();}3.预编译写法：
EntityManager em = getEm();String getAllTask = "SELECT ID,DEPARTMENT,WBS,CODE,NAME,PARENT_CODE FROM GAEI_WORK_TASK" +" WHERE WBS = ? AND DEPARTMENT = ? ";Query query = em.createNativeQuery(getAllTask);query.setParameter(1, wbs);query.setParameter(2, ((Department) userService.getSecondDepartmentByUserId(uid)).getId());List<Object> taskList = query.getResultList();
4. 附上原本查询写法：（ 建议参数都改为走预编译 ）
String sql = " SELECT" +" pro.id," +" pro.CODE," +" pro.PROJECT_NAME," +" pro.PROJECT_DIRECTOR_NO 'PROJECT_DIRECTOR_NO.id'," +" pro.source," +" gaei_pro.WBS," +" app_user.fullname 'PROJECT_DIRECTOR_NO.fields'," +" gaei_pro.STATUS" +" FROM" +" GAEI_PROJECT pro" +" LEFT JOIN appbricks_user app_user ON gaei_pro.PROJECT_DIRECTOR_NO = app_user.id" +" WHERE app_user.id = '" + approveId + "'" +" ORDER BY pro.CODE ASC";List<Object> resultList = getResultList(em, sql);
// 执行查询public static <T> List<T> getResultList(EntityManager em, String sql) {List<T> resultList = em.createNativeQuery(sql).getResultList();return resultList;}
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