和count(*) 没关系, 我就是要把是null的部分换成0.select case when 列 is null then 0 else 列 end 这个when到底加在哪里?譬如: link了以后,有些CASE_NUMBER部分就为null,我现在要用0填充 ========= SELECT Customer_Info.*, ASSISTANT_GROUP_CASEINFO.CASE_NUMBER FROM Customer_Info LEFT JOIN ASSISTANT_GROUP_CASEINFO ON ASSISTANT_GROUP_CASEINFO.SHORTNAME = Customer_Info.SHORTNAME WHERE CUSTOMER_INFO.STATUS='顾问单位'; ==========
select case when 列 is null then 0 else 列 end
这个when到底加在哪里?譬如: link了以后,有些CASE_NUMBER部分就为null,我现在要用0填充
=========
SELECT Customer_Info.*, ASSISTANT_GROUP_CASEINFO.CASE_NUMBER
FROM Customer_Info LEFT JOIN ASSISTANT_GROUP_CASEINFO ON ASSISTANT_GROUP_CASEINFO.SHORTNAME = Customer_Info.SHORTNAME
WHERE CUSTOMER_INFO.STATUS='顾问单位';
==========