At 03:47 PM 31-10-01 +0000, Edwin wrote:

>Can I achieve this? If yes, what are the commands? Thanks.

There are no "commands". You can achieve different levels of row locking by setting various isolation levels and associated settings on transactions. Table locking is rare but you have several choices of parameters using a RESERVING clause on your transaction that specifies the table(s) and the levels of access permitted to other transactions.

You can get a "pessimistic lock" on a row by subjecting it to a dummy update before the user begins the real update work. (You have to watch out for your update triggers when doing this, to ensure that they don't fire twice...).

For info about transactions, see the Programmer's Guide, the API Guide and the Embedded SQL Guide of the beta manual set.

Perhaps you would like to post details of what you need to do and what environment you are using for application development.

Regards,
Helen

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InterBase Developer Initiative · http://www.interbase2000.org
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