How to check if a string is a uniqueidentifier?

Question

Is there an equivalent to IsDate or IsNumeric for uniqueidentifier (SQL Server)? Or is there anything equivalent to (C#) TryParse?

Otherwise I\'ll have to write my o

Answer 1

You can write your own UDF. This is a simple approximation to avoid the use of a SQL-CLR assembly.

CREATE FUNCTION dbo.isuniqueidentifier (@ui varchar(50))  
RETURNS bit AS  
BEGIN

RETURN case when
    substring(@ui,9,1)='-' and
    substring(@ui,14,1)='-' and
    substring(@ui,19,1)='-' and
    substring(@ui,24,1)='-' and
    len(@ui) = 36 then 1 else 0 end

END
GO

You can then improve it to check if it´s just about HEX values.