OdbcConnection : concurrent transaction, IsolationLevel

  • Thread starter Thread starter Hakùna kù
  • Start date Start date
H

Hakùna kù

Hello ,

I need help to How I Can serialize Query with .NetFramework
and Odbc SQLServer Connection ...

I want that :
1. Client A read "name,lastname" from query
2. Client B try to read "name,lastname" but .Net must block the query
3. Client B is waiting that client A have release the block
4. Client A update "name,lastname"
5. Client A close the transaction
6. Client B read "name,lastname" and exit from Block "state"
7. Client B is happy :-))

How I can do it ?!
OdbcTransaction can allow me to do it ?!

thank all

Hakù
 
Hakùna kù said:
Hello ,

I need help to How I Can serialize Query with .NetFramework
and Odbc SQLServer Connection ...

I want that :
1. Client A read "name,lastname" from query
2. Client B try to read "name,lastname" but .Net must block the query
3. Client B is waiting that client A have release the block
4. Client A update "name,lastname"
5. Client A close the transaction
6. Client B read "name,lastname" and exit from Block "state"
7. Client B is happy :-))

How I can do it ?!
OdbcTransaction can allow me to do it ?!
Click to expand...

Yes. Each client should enlist all Commands in a transaction.

Then if client A issues
SELECT name,lastname from t with(updlock) where id = ?

This will select one row and lock it for the duration of client A's
transaction.

David

David
 
Then if client A issues
SELECT name,lastname from t with(updlock) where id = ?

This will select one row and lock it for the duration of client A's
transaction.
Click to expand...

Hello ,

But :

myTransaction.BeginTransaction(IsolationLevel.ReadCommited);
myCommand.transaction = myTransaction;

What is ?
My code not lock the row/s affected of Query ?

And what is "updlock" ?
How I find documentation on this method ?

Hukù
 
Hakùna kù said:
Hello ,

But :

myTransaction.BeginTransaction(IsolationLevel.ReadCommited);
myCommand.transaction = myTransaction;

What is ?
My code not lock the row/s affected of Query ?

And what is "updlock" ?
Click to expand...

Use update locks instead of shared locks while reading a table, and hold
locks until the end of the statement or transaction. UPDLOCK has the
advantage of allowing you to read data (without blocking other readers) and
update it later with the assurance that the data has not changed since you
last read it.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/acdata/ac_8_con_7a_1hf7.asp
How I find documentation on this method ?
Click to expand...

SQL Books Online, or MSDN


David
 
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