笔记-Microsoft SQL Server 2008技术内幕：T-SQL语言基础-09 事务和并发

事务必须有四个属性：原子性、一致性、隔离性、持久性，这四个属性的首字母可以缩写为ACID。

以下代码定义了一个事务，插入新订单数据：

-- Start a new transaction
BEGIN TRAN;

  -- Declare a variable
  DECLARE @neworderid AS INT;

  -- Insert a new order into the Sales.Orders table
  INSERT INTO Sales.Orders
      (custid, empid, orderdate, requireddate, shippeddate, 
       shipperid, freight, shipname, shipaddress, shipcity,
       shippostalcode, shipcountry)
    VALUES
      (85, 5, '20090212', '20090301', '20090216',
       3, 32.38, N'Ship to 85-B', N'6789 rue de l''Abbaye', N'Reims',
       N'10345', N'France');

  -- Save the new order ID in a variable
  SET @neworderid = SCOPE_IDENTITY();

  -- Return the new order ID
  SELECT @neworderid AS neworderid;

  -- Insert order lines for new order into Sales.OrderDetails
  INSERT INTO Sales.OrderDetails
      (orderid, productid, unitprice, qty, discount)
    VALUES(@neworderid, 11, 14.00, 12, 0.000);
  INSERT INTO Sales.OrderDetails
      (orderid, productid, unitprice, qty, discount)
    VALUES(@neworderid, 42, 9.80, 10, 0.000);
  INSERT INTO Sales.OrderDetails
      (orderid, productid, unitprice, qty, discount)
    VALUES(@neworderid, 72, 34.80, 5, 0.000);

-- Commit the transaction
COMMIT TRAN;