What Is The Difference Between Lock, Block And Deadlock?

1.	What Is The Difference Between Lock, Block And Deadlock?
Answer» Lock: DB engine LOCKS the rows/page/table to access the data which is worked upon according to the QUERY. Block: When one process BLOCKS the resources of another process then blocking happens. Blocking can be identified by USING SELECT * FROM sys.dm_exec_requests where blocked <> 0 SELECT * FROM master..sysprocesses where blocked <> 0 Deadlock: When SOMETHING happens as follows: Error 1205 is reported by SQL Server for deadlock. Lock: DB engine locks the rows/page/table to access the data which is worked upon according to the query. Block: When one process blocks the resources of another process then blocking happens. Blocking can be identified by using SELECT * FROM sys.dm_exec_requests where blocked <> 0 SELECT * FROM master..sysprocesses where blocked <> 0 Deadlock: When something happens as follows: Error 1205 is reported by SQL Server for deadlock.

Answer»

Lock: DB engine LOCKS the rows/page/table to access the data which is worked upon according to the QUERY.

Block: When one process BLOCKS the resources of another process then blocking happens. Blocking can be identified by USING

SELECT * FROM sys.dm_exec_requests where blocked <> 0
SELECT * FROM master..sysprocesses where blocked <> 0

Deadlock: When SOMETHING happens as follows: Error 1205 is reported by SQL Server for deadlock.

Lock: DB engine locks the rows/page/table to access the data which is worked upon according to the query.

Block: When one process blocks the resources of another process then blocking happens. Blocking can be identified by using

SELECT * FROM sys.dm_exec_requests where blocked <> 0
SELECT * FROM master..sysprocesses where blocked <> 0

Deadlock: When something happens as follows: Error 1205 is reported by SQL Server for deadlock.

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