Oacle 日期函数的应用

 

Oracle 使用 months_between(ddd.s_date, S.VALID_BEGIN_DATE)  来计算月份的差值。

得出的是带小数的值。

 

 

 

 

SELECT P.PILOT_ID basicInfoId,
    P.CLERK_CODE clerkCode,
       P.PILOT_NAME pilotName,
       S.RETRAINING_PLACE comId,
       U.UNIT_NAME unitName,
       S.MONTH1 month1,
       S.MONTH2 month2,
       S.VALID_BEGIN_DATE validBeginDate,
       ddd.s_date,
       months_between(ddd.s_date, S.VALID_BEGIN_DATE) AS monthnum,
       CASE
         WHEN SUBSTR(NVL(S.TECHNICAL_STANDARD, '21'), 0, 1) = '1' THEN
          '机长'
         ELSE
          '副驾驶'
       END technicalStandard,
       S.NEXT_SCIAMACHY nextSciamachy,
       S.NEXT_SCIAMACHY_TEACHER nextSciamachyTeacher,
       S.TEACHER_STANDARD teacherStandard,
       S.SKILLED_INSPECTOR_STAND_DATE skilledInspectorStandDate,
       S.OFFICE_INSPECTOR_STAND_DATE officeInspectorStandDate,
       S.VALID_END_DATE validEndDate,
       S.LICENCE_END_DATE licenceEndDate,
       S.NEXT_TEACHER_NUM nextTeacherNum
       --S.MAIN_AC_TYPE_CODE mainAcTypeCode

  FROM sim_v_pilot P, dc.v_pilot_licence_standard S, flight.BD_AERO_UNIT U, dc.bd_ac_type a,
  
   (
   SELECT max(m.s_date) AS s_date, n.pilot_id
   FROM sim_training_sim m LEFT JOIN sim_student_assign n ON m.suite_id = n.suite_id
   WHERE m.ac_type_code = 14 GROUP BY n.pilot_id
   ) ddd 
   
   
 WHERE P.PILOT_ID = S.PILOT_ID
   AND U.UNIT_CODE = SUBSTR(P.ORG_CODE, 0, 4)
   AND S.MAIN_AC_TYPE_CODE = '14'
   and s.main_ac_type_code = a.ac_type_code
   AND P.WORK_TYPE = '5201'
   AND S.MONTH1 IS NOT NULL
   AND S.MONTH2 IS NOT NULL
   AND ddd.pilot_id = P.Pilot_Id
   AND S.NEXT_SCIAMACHY = 1
   AND (to_char(ddd.s_date, 'mm') - S.MONTH1 > 1 OR to_char(ddd.s_date, 'mm') - S.MONTH1 < -1)