can any tell what is the exact syntax to lock table in a database

[PHP]






ankurkaushik@gmail.com

according the doc :
-LOCK TABLE--+-table-name-+--IN--+-SHARE-----+--MODE---------><
'-nickname---' '-EXCLUSIVE-'

thanks for giving me suggestion its working

but after locking table i can select table ,insert data,alter ,delete
so what will be use of locking table??

That's exactly why you would lock the table: so that *you* can insert, delete, etc. in the table, while *others* cannot interfere.

suppose i connect to database as

connect to cricket user ism using ism

then

lock table bcci in share mode

now I can insert , update , delete etc to that table

even other user can also do by connecting that particular database
how can we apply bar to other user on that table by locking

Locks are released on commit. If you don't switch autocommit off (which I suspect is the case) your lock is released right after the LOCK statement is issued.

no i think this is not the case because autocommint is on

It's really easy to check: just take a locks snapshot after the LOCK statement.

can you tell in brief how we can check our autocommit status

yeah I got the command to check your auto commit status


but cant find find whats use of lock tables ?

If you acquire a lock in "shared" mode, then other users will be able to access the table and select from it. They won't be able to write to the table.

Different question: why exactly do you want to lock the table? DB2 (or any other decent DBMS) will take care of locking for you and your application should not even worry about it.

please make me clear why locking tables

First, you don't have to lock tables yourself.

Sometimes it may be beneficial to explicitly lock a table to prevent DB2 from acquiring row locks which may later on be escalated to a table lock. But this is something you only do if really necessary.