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How to check GUID is null or empty in SQL Server

Text version of the video http://csharp-video-tutorials.blogspo... Healthy diet is very important both for the body and mind. If you like Aarvi Kitchen recipes, please support by sharing, subscribing and liking our YouTube channel. Hope you can help.    / @aarvikitchen5572   Slides http://csharp-video-tutorials.blogspo... All SQL Server Text Articles http://csharp-video-tutorials.blogspo... All SQL Server Slides http://csharp-video-tutorials.blogspo... All SQL Server Tutorial Videos    • SQL Server tutorial for beginners   All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenka... All Dot Net and SQL Server Tutorials in Arabic    / kudvenkatarabic   In this video we will discuss how to check if a GUID is null or empty How to check if a GUID is NULL : Checking if a GUID is null is straight forward in SQL Server. Just use IS NULL keywords as shown below. Declare @MyGuid Uniqueidentifier If(@MyGuid IS NULL) Begin Print 'Guid is null' End Else Begin Print 'Guid is not null' End In the above example, since @MyGuid is just declared and not initialised, it prints the message "Guid is null" Now let's say, if a GUID variable is NULL, then we want to initialise that GUID variable with a new GUID value. If it's not NULL, then we want to retain it's value. One way to do this is by using an IF condition as shown below. Declare @MyGuid UniqueIdentifier If(@MyGuid IS NULL) Begin Set @MyGuid = NEWID() End Select @MyGuid We can achieve exactly the same thing by using ISNULL() function. The advantage of using ISNULL() function is that, it reduces the amount of code we have to write. Declare @MyGuid UniqueIdentifier Select ISNULL(@MyGuid, NewID()) How to check if a GUID is EMPTY : Before understanding how to check if a GUID is empty, let's understand what is an empty GUID. An empty GUID is a GUID with all ZEROS as shown below. 00000000-0000-0000-0000-000000000000 How to create this empty GUID. Do we have to type all the ZERO's and Hyphens. The answe is NO. We do not have to type them manually. Instead use one of the following SELECT query's to create an empty GUID. I prefer to use the second SELECT statement as it has only one CAST SELECT CAST(CAST(0 AS BINARY) AS UNIQUEIDENTIFIER) OR SELECT CAST(0x0 AS UNIQUEIDENTIFIER) To check if a GUID is an empty GUID, you have 2 options Option 1: You can compare it to an Empty GUID value as shown below Declare @MyGuid UniqueIdentifier Set @MyGuid = '00000000-0000-0000-0000-000000000000' If(@MyGuid = '00000000-0000-0000-0000-000000000000') Begin Print 'Guid is Empty' End Else Begin Print 'Guid is not Empty' End Option 2: You can also compare it to a return value of the CAST method Declare @MyGuid UniqueIdentifier Set @MyGuid = '00000000-0000-0000-0000-000000000000' If(@MyGuid = Cast(0x0 as Uniqueidentifier)) Begin Print 'Guid is Empty' End Else Begin Print 'Guid is not Empty' End