Using INT or GUID as primary key

Question

I tried to create a column IDon the VB.net SQL server that would provide a sequence of numbers for each new row created in the database. Therefore, to create an ID column, I used the following method.

select * from T_Users
ALTER TABLE T_Users     
ADD User_ID INT NOT NULL IDENTITY(1,1) Primary Key

Then I registered several usernames in the database and it worked fine. For example, the first six lines will be 1,2,3,4,5,6. Then I registered 4 more users the next day, but this time the ID numbers moved from 6 to A, a very large number, for example: 1,2,3,4,5,6,1002,1003,1004,1005. Then two days later I registered two more users, and new lines - 3002,3004. So my question is why it misses such a large amount every other day when I register users. Is the technique I used to create the sequence wrong? If this is wrong, can someone tell me how to do it right? Now that I have become disillusioned with the technique described above, I tried using sequentially generated GUID values.A sequence of GUID values ​​was generated by a penalty. However, the only drawback is that it generates very long numbers (4 times the size of INT). My question here is does the GUID take any significant advantage over INT?

Hello,

Answer 1

GUID Surface:

GUIDs are good if you ever want offline clients to be able to create new records, since you will never encounter a primary key when new records are synchronized with the main database.

Bottom side of the GUID:

GUIDS as primary keys can affect database performance, because for a clustered primary key, the database wants to keep the rows in the order of the key values. But that means a lot of insertions between existing entries, because the GUIDs will be random.

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