Re: ensuring row/table locking

[Aaron Westendorf <awestendorf@xxxxxxxxx>]

So I'm getting around to implementing the transaction isolation for our 
e-commerce section, and I need to be sure that it is going to work 
correctly.  The code I have in place does the following:

==========================================================
// Open connection
connection.setAutoCommit( false );
queryStatement = connection.prepareStatement( getStuffQuery );
// Setup query parameters

while(true) {
   // Query and test current value
   // If passed, update
   connection.commit();
   // If catch exception, continue through loop.  Else, break.
}
==========================================================

It's more elaborate than that, but you get the drift.  After 
implementing this and comparing notes with the transaction literature on 
the Mckoi website, I feel that the part before the loop may be wrong. 
It seems that the beginning (and end?) of a transaction is marked by the 
setAutoCommit() method.  If so, then do I need to open the connection, 
or at least call setAutoCommit(false), at the top of the loop?

-Aaron

Tobias Downer wrote:
> Databases such as Oracle, 
> PostgreSQL and Mckoi implement a versioning system that does not lock 
> any rows and allows multiple concurrent changes to a row, and detects 
> conflict at commit time.

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