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POSQl Server Express 2005 - updating 2 tables and atomicity?
 

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    <p>First off, I want to start by saying I am not an SQL programmer (I'm a C++/Delphi guy), so some of my questions might be really obvious. So pardon my ignorance :o)</p> <p>I've been charged with writing a script that will update certain tables in a database based on the contents of a CSV file. I have it working it would seem, but I am worried about atomicity for one of the steps: One of the tables contains only one field - an int which must be incremented each time, but from what I can see is not defined as an identity for some reason. I must create a new row in this table, and insert that row's value into another newly-created row in another table.</p> <p>This is how I did it (as part of a larger script):</p> <pre><code>DECLARE @uniqueID INT, @counter INT, @maxCount INT SELECT @maxCount = COUNT(*) FROM tempTable SET @counter = 1 WHILE (@counter &lt;= @maxCount) BEGIN SELECT @uniqueID = MAX(id) FROM uniqueIDTable &lt;----Line 1 INSERT INTO uniqueIDTableVALUES (@uniqueID + 1) &lt;----Line 2 SELECT @uniqueID = @uniqueID + 1 UPDATE TOP(1) tempTable SET userID = @uniqueID WHERE userID IS NULL SET @counter = @counter + 1 END GO </code></pre> <p>First of all, am I correct using a "WHILE" construct? I couldn't find a way to achieve this with a simple UPDATE statement.</p> <p>Second of all, how can I be sure that no other operation will be carried out on the database between Lines 1 and 2 that would insert a value into the uniqueIDTable before I do? Is there a way to "synchronize" operations in SQL Server Express?</p> <p>Also, keep in mind that I have no control over the database design.</p> <p>Thanks a lot!</p>
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