For UPDATE, INSERT, and DELETE statements, the return value is the number of rows affected by the command. When a trigger exists on a table being inserted or updated, the return value includes the number of rows affected by both the insert or update operation and the number of rows affecte...
( CASE WHEN SalariedFlag = 0 THEN VacationHours + @NewHours ELSE @NewHours END ) WHERE CurrentFlag = 1; SET @RowCount = @@ROWCOUNT; GO -- Execute the stored procedure and return the number of rows updated to the variable @RowCount DECLARE @RowCount int; EXECUTE HumanResources.Update_...
GO SELECT * FROM TestBatch; -- Returns rows 1 and 2. GO 锁定和行版本控制基本知识 当多个用户同时访问数据时,数据库引擎使用以下机制确保事务的完整性和保持数据库的一致性: 锁定 每个事务对所依赖的资源(如行、页或表)请求不同类型的锁。 锁可以阻止其他事务以某种可能会导致事务请求锁出错的方式修改资...
调用操作设置为 SQL_UPDATE 的 SQLSetPos,将 RowNumber 设置为要更新的行数。 如果 RowNumber 为0,将更新行集中的所有行。SQLSetPos 返回后,当前行将设置为更新的行。更新行集的所有行(RowNumber 等于0)时,应用程序可以通过将行操作数组(由 SQL_ATTR_ROW_OPERATION_PTR 语句属性指向)的相应元素设置为...
此缓冲区的地址是使用 SQL_ATTR_ROWS_FETCHED_PTR 语句属性指定的。 缓冲区由应用程序分配。 它由SQLFetch和SQLFetchScroll设置。 如果 SQL_ATTR_ROWS_FETCHED_PTR 语句属性的值是空指针,则这些函数不会返回提取的行数。 若要确定结果集中当前行的数目,应用程序可以使用 SQL_ATTR_ROW_NUMBER 属性调用SQLGetStmtAtt...
EXECUTE AS USER = 'Sales2'; SELECT * FROM Sample.Sales; -- This will return just the rows for Product 'Wheel' (as specified for 'Sales2' in the Lk_Salesman_Product table above) REVERT; EXECUTE AS USER = 'Manager'; SELECT * FROM Sample.Sales; -- This will return all rows with no...
本文介绍如何使用SqlDataAdapter对象更新 Microsoft Visual C++中的 SQL Server 数据库。 原始产品版本:Visual C++ 原始KB 编号:308510 总结 该SqlDataAdapter对象充当 ADO.NETDataSet对象和 SQL Server 数据库之间的桥梁。 它是一个中间对象,可用于执行以下操作: ...
Use the @@ROWCOUNT function to return the number of inserted rows to the client application. For more information, see @@ROWCOUNT (Transact-SQL).Variable names can be used in UPDATE statements to show the old and new values affected, but this should be used only when the UPDATE statement ...
Count The Number Of Rows Inserted Per Day Count(*) with Partition by producing the wrong result. Count(Distinct): missing operator error? Counting Blank spaces between two words in string Counting Carriage returns Counting the '-' (Hyphens) in a string Country, State and City SQL Database Co...
In an AFTER UPDATE trigger where at least one row was updated, both the inserted and deleted tables will contain the same number of rows. In an AFTER DELETE trigger, only the deleted table will contain data since there are no new values. On the other hand, in an AFTER INSERT trigger, ...