Kindly help with this problem

Primary keys in a database?

Is it in Access or MySql?

On a table let's say users, you have may be userid, name, email, password

Primary key and unique key are more like same


You can set the user I'd to auto increment then set it as a primary key so two users can not have the same userid, it is just a unique way of identify a row in a table.
You can also set the username or email to be the primary key, so no user can have the same unsername.

When creating a table you just add:

Primary key (email)

Or if you already have the table, just alter it

ALTER TABLE users ADD PRIMARY KEY (email)

You may also want to know what secondary keys are.

Sorry, if you set for example user id to auto increment, automatically it is a unique key because nobody can have the same id.

But in a place for example a student database system where you want to give every student an enroll number, that must be set as primary key.

Thanks so much for your concern. I got it. God bless u.

Deji Adewumi: Kindly help with this problem

Primary keys are fields/attributes that you use to uniquely identify an item.

Let's say, for example, you have a database that manages student information in a particular school. Each student could have different fields/attributes like first name, last name, surname, date of birth etc... Chances are that 2 students might end up bearing identical names and this could cause problems later on.

To avert such a scenario, a new attribute could be introduced - say a registration number or id number. This attribute/field will uniquely identify each student so that even students with identical names end up having a unique identifier.

---

To the second part of your question, what database are you using?