How to generate a new Guid in stored procedure?

sql

guid

stored-procedure

best-practices

byAnton Shumikhin·Aug 12, 2024

Generate a new GUID in SQL with NEWID():

SELECT NEWID();

This simple command instantly spawns a unique identifier. Slip it into your queries or stored procedures as needed.

Diving deep into GUID generation

Creating a unique identifier, or GUID, is fundamental for ensuring truly distinguishable rows in databases like SQL Server and Oracle. NEWID() is your buddy in SQL Server, while the Oracle equivalent goes by SYS_GUID().

Embracing cross-platform compatibility

If you happen to be a MySQL user, you'll need to get acquainted with the UUID() function instead:

SET @id = UUID();

Now, @id is charged with a brand new GUID for you to deploy at your will.

Weighing performance implications

Using a GUID as a primary key might have its drawbacks concerning performance due to its larger size and randomness impacting indexing. An identity column might be your savior ensuring sequential growth which can be more efficient.

Friendly rivalry: GUID vs. Identity

GUIDs are the prom kings for universally unique identifiers but don't forget the trade-offs. Will Pauline GUID still be prom queen with her index fragmentation, or will sporty sequential Identity win the day?

GUID generation in action

A walk in the park: adding a freshly minted GUID to a table during insertion via a stored procedure.

CREATE PROCEDURE InsertWithNewGuid
AS
BEGIN
    DECLARE @NewID UNIQUEIDENTIFIER = NEWID(); -- GUID born, confetti please!
    INSERT INTO YourTable(id, other_columns)
    VALUES (@NewID, other_data); -- GUID enters the stage
END

The generation and utilization of the GUID are elegantly separated, offering you flexibility if you need to deploy it for multiple operations within the same act.

Déjà vu with GUIDs

Sometimes, you might need to reuse a GUID across several tables. Do it as follows:

SELECT @NewID as ReusedGUID; --GUID clones itself. There's more than enough of it to go around.

Best practices and troubleshooting

Even with creating and using GUIDs seeming simple enough, always adhere to these best practices and troubleshooting tips to prevent stepping on that banana peel:

Testing: Verify Twice, Insert Once

Testing your stored procedure before launching will save you from subtly introduced GUID collisions that can cause pandemonium in your dataset.

Compatibility: Not Every Database is Your Buddy

Make sure that your used database system is co-operating with your fave GUID generation functions. It may throw syntax tantrums or even downright refuse to recognize your familiar functions.