求SQL语句的写法,大师们
求SQL语句的写法,大师们,求救
表名 Node
字段 Guid,FatherGuid,NodeName
这个表储存一个节点,FatherGuid为父节点的Guid,例如
Node1 "0","","父节点"
Node2 "1","0",“子节点A”
Node3 "2","0",“子节点B”
想通过一条SQL语句,获取以下结果
Guid FatherGuid NodeName FatherNodeName
1 0 子节点A 父节点
2 0 子节点B 父节点
------解决思路----------------------
SELECT
A.Guid,A.FatherGuid,A.NodeName,B.NodeName AS FatherNodeName
FROM
Node A LEFT JOIN Node B ON A.FatherGuid=B.Guid
WHERE A.FatherGuid=0
类似这样
表名 Node
字段 Guid,FatherGuid,NodeName
这个表储存一个节点,FatherGuid为父节点的Guid,例如
Node1 "0","","父节点"
Node2 "1","0",“子节点A”
Node3 "2","0",“子节点B”
想通过一条SQL语句,获取以下结果
Guid FatherGuid NodeName FatherNodeName
1 0 子节点A 父节点
2 0 子节点B 父节点
------解决思路----------------------
SELECT
A.Guid,A.FatherGuid,A.NodeName,B.NodeName AS FatherNodeName
FROM
Node A LEFT JOIN Node B ON A.FatherGuid=B.Guid
WHERE A.FatherGuid=0
类似这样