有两个具有相同结构的表,如SQLFiddle,是否可以构建一个SQL语句来比较两个表的列的值(其中id是唯一键),并在格式返回变更列的列表:比较和合并来自2个具有相同结构的表的数据
columnname, oldvalue, newvalue
凡oldvalue
是Table1
和newvalue
值在Table2
值。
有两个具有相同结构的表,如SQLFiddle,是否可以构建一个SQL语句来比较两个表的列的值(其中id是唯一键),并在格式返回变更列的列表:比较和合并来自2个具有相同结构的表的数据
columnname, oldvalue, newvalue
凡oldvalue
是Table1
和newvalue
值在Table2
值。
你可以做这样的事情:
SELECT T1.Id
,'Name' AS ColumnName
,CAST(T1.name AS VARCHAR(MAX)) AS OldValue
,CAST(T2.name AS VARCHAR(MAX)) AS NewValue
FROM Table1 AS T1
FULL OUTER JOIN Table2 AS T2
ON T1.id = T2.id
UNION
SELECT T1.Id
,'Amount'
,CAST(T1.amount AS VARCHAR(MAX))
,CAST(T2.amount AS VARCHAR(MAX))
FROM Table1 AS T1
FULL OUTER JOIN Table2 AS T2
ON T1.id = T2.id
您需要使用MERGE语句,请注意它只能从SQL 2008年起
这里有一个例子
MERGE Production.ProductInventory AS target
USING (SELECT ProductID, SUM(OrderQty) FROM Sales.SalesOrderDetail AS sod
JOIN Sales.SalesOrderHeader AS soh
ON sod.SalesOrderID = soh.SalesOrderID
AND soh.OrderDate = @OrderDate
GROUP BY ProductID) AS source (ProductID, OrderQty)
ON (target.ProductID = source.ProductID)
WHEN MATCHED AND target.Quantity - source.OrderQty <= 0
THEN DELETE
WHEN MATCHED
THEN UPDATE SET target.Quantity = target.Quantity - source.OrderQty,
target.ModifiedDate = GETDATE()
OUTPUT $action, Inserted.ProductID, Inserted.Quantity, Inserted.ModifiedDate, Deleted.ProductID,
Deleted.Quantity, Deleted.ModifiedDate;
GO
你可以在这里了解更多关于合并的信息SQL merge
这是什么?这不会产生所需的输出,甚至不会使用提供的表模式。 – dario 2015-03-13 14:18:32
如果您只想要有差异的行:
SELECT COALESCE(T1.Id, T2.Id) Id
,'Name' AS ColumnName
,CAST(T1.name AS VARCHAR(MAX)) AS OldValue
,CAST(T2.name AS VARCHAR(MAX)) AS NewValue
FROM Table1 AS T1
FULL OUTER JOIN Table2 AS T2
ON T1.id = T2.id
WHERE COALESCE(T1.name,'**') != COALESCE(T2.name ,'**')
UNION ALL
SELECT COALESCE(T1.Id, T2.Id) Id
,'Amount' AS ColumnName
,CAST(T1.Amount AS VARCHAR(MAX)) AS OldValue
,CAST(T2.Amount AS VARCHAR(MAX)) AS NewValue
FROM Table1 AS T1
FULL OUTER JOIN Table2 AS T2
ON T1.id = T2.id
WHERE COALESCE(T1.Amount,0) != COALESCE(T2.Amount,0)
提示:使用合适的软件(MySQL,Oracle,DB2,...)和版本(例如, '的SQL服务器2014'。语法和功能的差异往往会影响答案。 – HABO 2015-03-13 13:51:00