(i) USE Database: This command is used to select the database in MySQL for working.
Syntax:
mysql>use test:
Database changed
mysql>
(ii) SHOW Database: Lists all the databases available in the database server.
Syntax:
mysql>show databases;
(iii) SHOW Tables: Lists all the tables available in the current database we are working in.
Syntax: mysql>show tables;

List of privileges available in MySQL

Privileges	Action Performed (If Granted)
Select_priv	User can select rows from database tables.
Insert_priv	User can insert rows into database tables.
Update_priv	User can update rows of database tables.
Delete_priv	User can delete rows of database tables.
Create_priv	User can create new tables in database
Alter_priv	User can make changes to the database structure.

Cardinality is defined as the number of items that must be included in a relationship (i.e) number of entities in one set mapped with the number of entities of another set via the relationship The three classifications in Cardinality are one-to-one, one-to-many and Many-to-Many.
In the above example we have two entities Person and Vehicle. If we consider a person driving vehicle, then we have one-to-one relationship between Person and Vehicle.
In the above example, Customer places the Order is a one-to-many relationship. Here the customer can place multiple orders and the order is related to only one customer.
The example of many-to-many relationship is Students registering the Courses. A student can register more than one courses and A course can be registered by many students. Hence it is many-to-many.

In ER Model, relationship exists between two entities. Three types of relationships are available and the Entity-Relationship (ER) diagram is based on the three types listed below
(i) One-to-One relationship: Consider two entities A and B. One-to-one (1:1) relationship is said to exist in a relational database design, if 0 or 1 instance of entity A is associated with 0 or 1 instance of entity B, and 0 or 1 instance of entity B is associated with 0 or I instance of entity A.
(ii) One-to-Many relationship: Consider two entities A and B. One-to-many (1:N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, but for 1 instance of entity B there exists 0 ur 1 instance of entity A.
(iii) Many-to-Many relationship: Consider two entities A and B. many-to-many (M:N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, and for 1 instance of entity B there exists 0 or 1 or many instance of entity A.

Evolution of DBMS:
(i) The concept of storing the data started before 40 years in various formats.
(ii) In earlier days they have used punched card technology to store the data. Then files were used.
(ii) The file systems were known as predecessor of database system.
(iv) Various access methods in file system were indexed, random and sequential access.
The file system had more limitations like.
Data Duplication : Same data is used by multiple resources for processing, thus created multiple copies of same data wasting the spaces.
High Maintenance : Access control and verifying data consistency needs high maintenance cost.
Security : Less security provided to the data.
(v) So database systems became popular to overcome the above limitations of file system.