如何在我的sql表中获取数据时显示0而不是NULL

Question

我取出由MySQL表数据它工作正常,但它显示NULL了Status在两个领域.我想要而不是NULL表演0.

这是我的查询:

SELECT ml.GroupID, ml.GroupTitle, ml.GroupDescription, ml.GroupCreatedDateTime, ml.GroupOwnerUserID, ml.ApprovalNeeded, ml.GroupStatus, ml.OrganizationCode, cat.Status
FROM GroupsMaster AS ml
LEFT JOIN UserGroupsMapping cat ON cat.GroupID = ml.GroupID
WHERE ml.OrganizationCode = ?

Answer 1

使用COALESCE运算符

   COALESCE(cat.Status, 0)


SELECT 
 ml.GroupID, 
 ml.GroupTitle, 
 ml.GroupDescription, 
 ml.GroupCreatedDateTime, 
 ml.GroupOwnerUserID, 
 ml.ApprovalNeeded, 
 ml.GroupStatus, 
 ml.OrganizationCode, 
 COALESCE(cat.Status, 0) as Status 
FROM GroupsMaster AS ml 
LEFT JOIN UserGroupsMapping cat ON cat.GroupID = ml.GroupID 
WHERE ml.OrganizationCode = 'ibm'