需要关于嵌套CASE语句的帮助

Question

我需要在SQL中重写以下IF-THEN代码，下面是我的第一次尝试。但是当我运行SQL代码时，它返回了一条错误消息：ORA-00933：SQL命令未正确结束。任何人都可以请帮忙？

此外，我想知道是否有更好的替代方法来重写SAS代码，而不是使用嵌套的Case语句。我是SQL的新手。任何帮助将不胜感激！

/********************** SAS代码****************** *****/

if Record_type = 'Cliam'and Claim_Type_E0141 in ('C','H','M','F','I','N','K','Z') THEN DO; 
if POS in ('21','22','23','24','25','26','27','28') then POS_new=31; 
if POS in ('86') then POS_new=32; 
if POS in ('81','82') then POS_new=34; 
('61','62','63','64','65','66','67','68') then POS_new=54; 
END; 

if Record_type = 'Encounter'and ENCOUNTER_TYPE_H054 in ('I') THEN DO; 
if BILL_TYPE_CODE_1_2 in ('21','22','23','24','25','26','27','28') then POS_new=31; 
if BILL_TYPE_CODE_1_2 in ('86') then POS_new=32; 
if BILL_TYPE_CODE_1_2 in ('81','82') then POS_new=34; 
if BILL_TYPE_CODE_1_2 in ('61','62','63','64','65','66','67','68') then POS_new=54; 
END; 

/*********************** SQL代码******* ****************/

UPDATE ALL_INPT 
SET POS_new = 
    WHEN Record_type = "Claim" and Claim_Type_E0141 in ('C','H','M','F','I','N','K','Z') 
      THEN CASE 
       WHEN POS in ('21','22','23','24','25','26','27','28') 
         THEN '31' 
       WHEN POS in ('86') 
         THEN '32' 
       WHEN POS in ('81','82') 
         THEN '34' 
       WHEN POS in ('61','62','63','64','65','66','67','68') 
         THEN '54' 
       ELSE POS 
      END 

    WHEN Record_type = "Encounter" and ENCOUNTER_TYPE_H054in ('I') 
      THEN CASE 
       WHEN BILL_TYPE_1_2_E0394 in ('21','22','23','24','25','26','27','28') 
         THEN '31' 
       WHEN BILL_TYPE_1_2_E0394 in ('86') 
         THEN '32' 
       WHEN BILL_TYPE_1_2_E0394 in ('81','82') 
         THEN '34' 
       WHEN BILL_TYPE_1_2_E0394 in ('61','62','63','64','65','66','67','68') 
         THEN '54' 
       ELSE BILL_TYPE_1_2_E0394 
      END     
END 

;

Answer 1

内部case在两种情况下都是相同的。我会将其简化为：

UPDATE ALL_INPT 
    SET POS_new = (CASE WHEN Record_type = 'Claim' and Claim_Type_E0141 in ('C','H','M','F','I','N','K','Z') OR 
          Record_type = 'Encounter' and ENCOUNTER_TYPE_H054 in ('I') 
         THEN (CASE WHEN POS in ('21','22','23','24','25','26','27','28') 
            THEN '31' 
            WHEN POS in ('86') 
            THEN '32' 
            WHEN POS in ('81','82') 
            THEN '34' 
            WHEN POS in ('61','62','63','64','65','66','67','68') 
            THEN '54' 
            WHEN Record_type = 'Claim' 
            ELSE BILL_TYPE_1_2_E0394 
           END) 
         ELSE pos_new     
        END); 

SAS代码中没有else子句。但是，如果没有条件满足，则pos_new的值不变。您的版本将值设置为NULL（如果这是原始值，则可能没有区别）。