SELECT * FROM table ROWLOCK WHERE id = 1 2 锁定数据库的一个表 SELECT * FROM table WITH (HOLDLOCK) 加锁语句: sybase: update 表 set col1=col1 where 1=0 ; MSSQL: select col1 from 表 (tablockx) where 1=0 ; oracle: LOCK TABLE 表 IN EXCLUSIVE MODE ; 加锁后其它人不可操作,直到加...
自SQL Server 2008开始,你可以控制SQL Server如何进行锁升级——通过ALTER TABLE语句和LOCK_ESCALTATION属性。有3个可用选项: TABLE AUTO DISABLE --Controllling Lock EscalationALTERTABLEPerson.PersonSET(LOCK_ESCALATION=AUTO--or TABLE or DISABLE)GO 默认选项是TABLE,意味着SQL Server总是执行锁升级到表层级——...
[LOW_PRIORITY] WRITE lock:The session that holds the lock canreadandwrite thetable.Onlythe session that holds the lock can access thetable.Noother session can access it until the lockisreleased.Lock requestsforthetablebyother sessions block while the WRITE lockisheld.The LOW_PRIORITY modifier has...
此选项被选中时,SQL Server 会将此共享锁保持至整个事务结束,而不会在途中释放。 SELECT * FROM table WITH (HOLDLOCK) 其他事务可以读取表,但不能更新删除 1. 2. 3. UPDLOCK(修改锁) 此选项被选中时,SQL Server 在读取数据时使用修改锁来代替共享锁,并将此锁保持至整个事务或命令结束。使用此选项能够保证多...
These locks are saved in a hash table in the server and implemented with pthread_mutex_lock() and pthread_mutex_unlock() for high speed. See Section 14.14, “Locking Functions”. See Section 10.11.1, “Internal Locking Methods”, for more information on locking policy. ...
在SQL Server中,普通的表值函数(table-valued function)是可以使用表提示(Hints-Table)的,那么CLR类型的表值函数(table-valued function)是否也可以使用表提示(Hints-Table)呢? 相信很多人都没有留意过这个问题。 下面我以YourSQLDba中现成的CLR表值函数来演示一下这个问题。如果自己手头有自定义CLR表值函数的,也...
RID= Lock on a single row in a table identified by a row identifier (RID). KEY= Lock within an index that protects a range of keys in serializable transactions. PAG= Lock on a data or index page. EXT= Lock on an extent. TAB= Lock on an entire table, including all data and indexe...
This issue occurs because the NOLOCK hint causes the query to incorrectly read values in the table when the query reads the same values multiple times. Resolution The issue was first fixed in the following cumulative update of SQL Server. ...
sp_refreshsqlmodule sp_refreshview sp_releaseapplock sp_rename sp_renamedb sp_resetstatus sp_rxpredict sp_sequence_get_range sp_server_diagnostics sp_set_session_context sp_setnetname sp_settriggerorder sp_spaceused sp_tableoption sp_unbindefault ...
sp_refreshsqlmodule sp_refreshview sp_releaseapplock sp_rename sp_renamedb sp_resetstatus sp_rxpredict sp_sequence_get_range sp_server_diagnostics sp_set_session_context sp_setnetname sp_settriggerorder sp_spaceused sp_tableoption sp_unbindefault ...