Re: transaction and open table

"Ryan Liu" <RyanLiu_99@xxxxxxxxx> wrote in message news:eloYgRotHHA.1184@xxxxxxxxxxxxxxxxxxxxxxx
I have few db write and read to execute, so I use transaction.

Is that a problem or is that a regular way that I only use transaction on
some cmds only, and other cmds I do not use trasaction, esp those read
actions, or even use another dbconnection to read?

It depends on what you are trying to accomplish. If the transaction is properly isolated (which you control through the transaction isolation level), then those commands that you execute outside of the transaction will not see the changes that you have done inside the transaction until the transaction is committed. This may or may not be what you want to happen.
Moreover, since the transaction will place locks on the database to accomplish the isolation, depending on what you are doing you risk that the database commands that you are executing outside of the transaction might get blocked waiting for the transaction to finish. You certainly don't want this to happen, because the blocked command would stop your program from proceeding to complete the transaction, and therefore would never get unblocked.


BTW, what does "open table" menas? Is that table only be "open" when someone
read or write it. Once all user finish read or write the db table, the
table should be "closed", is that right?

If you are sending Sql commands to a database, then the tables are not 'open' or 'closed'. They simply get some locks placed upon them when they are accessed inside a transaction, and the locks are removed when the transaction completes. This is automatic, and you don't have to do anything special for it to happen.

.

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