All attributes (columns) must be of the same domain: In other words, they must have the same data type.Rather, the database will understand that the value of that cell is exactly what has been entered. Each cell (field) must contain a single value: For example, you can't enter something like "Tom Smith" and expect the database to understand that you have a first and last name.
The key cannot have a NULL value, which means that the value must be known. This means that no tuple can have the same unique, primary key.
#Mysql database server terminology software#
A database server consists of hardware and software that run a database. It is a crucial component in the client-server computing environment where it provides business-critical information requested by the client systems. Its name must be unique in the database: A database cannot contain multiple tables of the same name. MySQL is an Open Source relational database Management System. A database server is a machine running database software dedicated to providing database services.