SQL Server Performance Forum – Threads Archive
Need some help on table locking with VB.NET
Hi, I’m quite inexperienced with SQL Server 2000 but I have to write an application on it for my job, in VB.NET. Basically what I will have is the following: Several client computers will poll a specific database table each x seconds. It’s in fact a table which contains jobs that the client computers must execute. What I need to do, as described in the concept of the application by our analyzer, is when a client polls the table, it locks the full table (so no other client can read nor change data anymore), selects the records it needs, updates those records (setting a field from busy = 0 to busy = 1), and then unlocks the table so that other clients can access it to poll for their collection of jobs which are not busy. How can this be achieved ?I’m using the SQLConnection object from .NET. I have no experience in any Transact-SQL syntax. The only thing I do is writing plain SQL queries from my .NET code to be executed by the SQLConnection object (with a DataAdapter etc.). Thank you for your answers ! Kind regards, Mathieu
well ado provides a locking machanism called adlockpessimistic which locks the table as soon as it is selected.
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