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cesark
Posting Yak Master
215 Posts |
 Posted - 2003-09-15 : 11:21:08
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Hi!  I want to create a uniqueidentifier data type in a existing table but i can't. I write the syntax as follows:ALTER TABLE UsersALTER COLUMN User_Id (uniqueidentifier NOT NULL DEFAULT NEWID())What is wrong?Another question is; I use a stored procedure to do new inserts in a table and to write the same generated identity to other tables which needed. This sp use a variable to store the newid generated retrived by the @@Identity (SELECT @NewId=@@Identity). What function is it better to retrieve the last identity and to ensure that is the real last generated? @@Identity, SCOPE_IDENTITY or IDENT_CURRENT. Which is the difference between these?.In my application will have many users at the same time inserting data and they will not still be registered.Cesar |
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AndrewMurphy
Master Smack Fu Yak Hacker
2916 Posts |
Posted - 2003-09-15 : 11:30:16
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| I suspect the problem is your default value NEWID().....which may not match your column data-type.try ALTER TABLE UsersALTER COLUMN User_Id (uniqueidentifier)on an empty USERS table....if this works....it's the default value that is giving you a problem. |
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cesark
Posting Yak Master
215 Posts |
Posted - 2003-09-15 : 12:14:39
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| Good! The problem was solved.What about my last doubt:I use a stored procedure to do new inserts in a table and to write the same generated identity to other tables which needed. This sp use a variable to store the newid generated retrived by the @@Identity (SELECT @NewId=@@Identity). What function is it better to retrieve the last identity and to ensure that is the real last generated? @@Identity, SCOPE_IDENTITY or IDENT_CURRENT. Which is the difference between these?.In my application will have many users at the same time inserting data and they will not still be registered.Thanks,Cesar |
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AndrewMurphy
Master Smack Fu Yak Hacker
2916 Posts |
Posted - 2003-09-17 : 06:59:52
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| forum search for SCOPE_IDENTITY,IDENT_CURRENT (either word OPTION) and several topics can be examined in which this has come up before....IDENT_CURRENT seems to be related to SQL2K.one of the topics is...http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=21283also BOL is pointed to as a information source in explaining this.having multiple users all running the same SP at the same time, will give independant results to each user....there should be no cross contamination of data.this link (http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=29208) gives a detailed explaination of the reason for using SCOPE_IDENTITY v @@IDENTITY |
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jeffreymfischer
Starting Member
10 Posts |
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To create a uniqueidentifier data type and...