如何使用JPA查询生成器在SQL中使用日期函数

Question

I am using following code to search table records based on the date but I am getting error while using the date function to_char

public List<TeacherTaskAllocation> searchTasks(String TeacherName, Date OnDate){
    EntityManager em=getEntityManager();
    try{
        CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery cq   = cb.createQuery(TeacherTaskAllocation.class);
        Root<TeacherTaskAllocation> rt = cq.from(TeacherTaskAllocation.class);
         cq.select(rt);
         List<Predicate> conditionList =new ArrayList<Predicate>();
         Predicate condition1,condition2;

         if((TeacherName!=null)&&(!(TeacherName.isEmpty()))){

             condition1=cb.like(cb.upper(rt.<String>get("teacherName")),"%"+TeacherName.toUpperCase()+"%" );

             conditionList.add(condition1);
         }

          if((OnDate!=null)&&(!(TeacherName.isEmpty()))){

          condition2=cb.equal((cb.function("TO_CHAR", "onDate", "dd/Mm/yy")), "%"+OnDate+"%");



             conditionList.add(condition2);
         }
          Predicate[] conditions = new Predicate[conditionList.size()];
          conditionList.toArray(conditions);
          cq.where(conditions); 
          TypedQuery<TeacherTaskAllocation> q = em.createQuery(cq);
          List<TeacherTaskAllocation> list=q.getResultList();
           return list;

    }finally{
        em.close();
    }`

Please can any one suggest me how I can achieve this task, how to use cb.function() in the jpa query builder

Answer 1

You should compare your param as a date with the date in database, not your param as a string compared to the database date as a string.

Use TO_DATE( string1, [ format_mask ], [ nls_language ] )