1. Almost same as English.


2. Easy to understand and learn.


3. Works with all the RDBMS systems currently available.


4. Many tools are available to auto generate SQL.

  Let’s take an example:
      Select Employ_Name
                        From Employ
This query will retrieve the names of employee from the table EMPLOY.

Classification of SQL
The SQL is basically divided into three parts.

1. Data Definition Language(DDL)

DDL statements are used to build and modify the structure of your tables and other objects in the database.
Let’s take an example:
create table Student
                (st_name char (20),
                                             st_add char (30),
                                             st_course char (10),
                                             st_rollno numeric(10),
                                              primary key (st_rollno))
This query will create the table in database with fields St_name, st_add, st_course, st_rollno, and will make the st_rollno primary key of table Student.

2. Data Manipulation Language (DML)
   

DML is used to retrieve, insert, delete and update data in database.

3. Data Control Language (DCL)


DCL is a subset of SQL, used to control access to data in a database.