I have a prolem of it. does it have upper boundary of auto-increase?if has, how I change to let it has not upper boundary
I assume you’re referring to identity columns. SQL Server ensures that a unique, incremental value is provided when a row is added.
The identity column’s value is limited only by the numeric limits of the type you choose and the seed and increment values you specify. Consider the following:
MyIdentity int identity (1, 1)
Values will be assigned beginning with 1 and increasing to an upper limit of 2,147,483,647. If you’re concerned about running out you have two options: (a) increase the size of the column (e.g. use bigint) or (b) use a seed value less than 1. For example, to get the most out of the identity column without increasing its size you can use the following:
MyIdentity int identity (-2147483648, 1)
If this is still too prohibitive then you may want to consider using the uniqueidentifier type.
Cheers,
Kenny Kerr
http://weblogs.asp.net/kennykerr/
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