Primary Key Can be Zero, but if you set Identity on the column it normally will start at 1 rather than Zero. Primary Key will have Identity Column ..
Can primary key be 0 MySQL?
Specifically, if you use 0 in an INSERT for a primary key, MySQL interprets that as a request to generate a new key.
Is primary key always a number?
The primary key should be numeric or date (avoid the use of text data types). Because it takes longer for the database to compare string values than numeric values, using text columns as primary keys is likely to degrade query performance.
Does a primary key have to start at 1?
Not all primary keys have to start at 1, as in the case of an order number. If the PK’s are starting from different ranges then it helps in testing reports.
