What is blocking and how would you troubleshoot it?



What is blocking and how would you troubleshoot it?..

Answer / monal

BLOCKING MEANS ONE PROCESS HAS LOCKS ON ONE OR MORE RECORDS
AND ANOTHER PROCESS TRIES TO ACQUIRE LOCK ON THE SAME SET OF
ROWS. SO BASICALLY SECOND PROCESS HAS TO WAIT TILL FIRST
PROCESS FINISH WORKING ON THE RECORDS AND THEN SECOND
PROCESS CAN TAKE OVER AND FINISH IT'S TASK. BLOCKING IS
DIFFERENT THEN DEADLOCK. BLOCKING CAN LAST LONGER AS IT IS
NOT AUTOMATICALLY STOPPED BY SQL SERVER LIKE DEADLOCK.

HERE'S GOOD SITE WHERE YOU CAN FIND INFO ABT BLOCKING.
http://www.builderau.com.au/program/sqlserver/soa/Find-blocking-processes-using-recursion-in-SQL-Server-2005/0,339028455,339286600,00.htm

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