SQL Server Performance Forum – Threads Archive
explain LCK_M_S
Hi, I am using sql server 2000. while running my application, some times the row is locked.When the row is locked, i have used dbcc opentran command in the query analyzer, the below shown reslt is displayed. Oldest active transaction:
SPID (server process ID) : 64
UID (user ID) : 1
Name : implicit_transaction
LSN : (1607:65:1)
Start time : Feb 24 2006 12:24:06:560PM so can u tell me, 64 is the blocking process ? and i have used dbcc inputbuffer(64), it displays a query… is this query blocking the other processes? i have checked the lock type is LCK_M_S … why this lock is occured? what are situations they are occured? how to prevent it? thanks
to quote BOL
quote:
Shared Locks
Shared (S) locks allow concurrent transactions to read (SELECT) a resource. No other transactions can modify the data while shared (S) locks exist on the resource. Shared (S) locks on a resource are released as soon as the data has been read, unless the transaction isolation level is set to repeatable read or higher, or a locking hint is used to retain the shared (S) locks for the duration of the transaction.
Shared Locks
Shared (S) locks allow concurrent transactions to read (SELECT) a resource. No other transactions can modify the data while shared (S) locks exist on the resource. Shared (S) locks on a resource are released as soon as the data has been read, unless the transaction isolation level is set to repeatable read or higher, or a locking hint is used to retain the shared (S) locks for the duration of the transaction.
—
Frank Kalis
Microsoft SQL Server MVP
http://www.insidesql.de
Heute schon gebloggt?http://www.insidesql.de/blogs
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