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實現方式 ：

1. 注入em:

  @PersistenceContextprivate EntityManager entityManager;

注入方式 2：

  @PersistenceUnitprivate EntityManagerFactory emf;

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2. 得到em：

 private EntityManager getEm() {return this.entityManager;}

對應第2種注入方式：

  /*** 得EntityManager** @return*/private EntityManager getEm() {return emf.createEntityManager();}

3.預編譯寫法：

   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. 附上原本查詢寫法：（ 建議參數都改為走預編譯 ）

 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);

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 // 執行查詢public static <T> List<T> getResultList(EntityManager em, String sql) {List<T> resultList = em.createNativeQuery(sql).getResultList();return resultList;}

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