UniqueIdentifier to Primary key

UniqueIdentifier is a Guid and cannot be convertet to an int. But if you add a new column INT and set it as primary key and is identity the database will give all rows a new id (int) And you can keep you UniqueIdentifier column or just delete it.. (unless it has a lot of relations...)

Uniqueidentifier is used to generate a surrogate key[^] and it contains both characters and numbers so it cannot be converted to any number data type.

If you want to convert it to something, you can use character datatypes, for example nvarchar. However, you normally shouldn't need to convert it to anything special since the only purpose of unique identifier is to identify a single record.

If you're looking for the .Net equivalent data type for parameters, you can use SqlDbType.UniqueIdentifier. See: SqlDbType Enumeration[^]

In my opinion keeping the primary key as an uniqueidentifier is an excellent choice, especially if replication is involved.