mfp: X++ Debugging Tips and Tricks #4 - Reading uncommitted data

[Blog bot]

Источник: http://blogs.msdn.com/b/mfp/archive/...tted-data.aspx
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This next trick in the X++ Debugging Tip and Tricks seriesis invaluable when stuck deep in a debugging session, and want to verify that the SQL statements being executed has the intended behavior.For illustrative purposes, I’ve created a small job. It updates the customer group to “40” for the customer with account number “4001”. This happens inside a transaction. I’ve also added a breakpoint statement to jump to the debugger inside the transaction.

When running the job the debugger opens:



Now, if we go the SQL Server Management Studio and execute a select statement to validate that the field was correctly updated, we will notice that it still has the old value:



This should not be a surprise, as the transaction has not been committed yet. However; that shouldn’t block our noble purpose. By adding the keyword “nolock” to the query, we instruct SQL to read the uncommitted data, and voila, we get the results we expect:



One additional piece of advice is related to more complicated SQL statements: You have to add the nolock keyword to every joined table.



This can be a true life saver when debugging. In fact I used this heavily the past few weeks where I've been working on the new Warehouse Management module in R3.




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Источник: http://blogs.msdn.com/b/mfp/archive/...tted-data.aspx

[Logger]

By adding the keyword “nolock” to the query, we instruct SQL to read the uncommitted data, and voila, we get the results we expect:...

Попробовал бы он такое в оракле провернуть
Фига с два. Но не будем о покойничке....

А еще этот способ бывает полезен, чтобы блокировки лишние не ставить при чтении. Правда с выходом уровнем изоляции транзакций Snapshot isolation мое замечание устарело.

[Wamr]

А можно и настройками запроса

[kashperuk]

Да. я обычно просто перед запросами в окне пишу

SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED

а то геморно как-то, nolock писать по двести раз