Platforms to lean SQL and copy SQL Dump to create sample student table with records and basics
Once our database and script installation is over then we can learn how to manage Database .
SQL ( Structured Query Language ) is one of the important tool for programmers. Sql is a part of the database management tool.
Types of SQL commands
DDL - Data Definition Language
DDL is used to define and manage the structure of a database and its objects.
CREATE, DROP, ALTER, TRUNCATE , COMMENT , RENAME
DML - Data Manipulation Language
DML is concerned with modifying and manipulating data stored in a database.
INSERT, UPDATE, DELETE
DQL - Data Query Language
DQL is specifically designed for querying and retrieving information from databases.
SELECT
DCL - Data Control Language
DCL includes commands that are responsible for granting or revoking permissions, privileges, and roles to users and roles, thus ensuring data security and access control
GRANT , REVOKE
TCL - Transaction Control Language
TCL is used for managing transactions within a database. A transaction is a sequence of one or more database operations (such as data manipulation or data definition) that are executed as a single unit of work.
COMMIT, ROLLBACK, SAVEPOINT, SET TRANSACTION
There are many databases available from different vendors. For web applications MSSQL, MySQL, SQLite are mostly used. Oracle is very popular among enterprise users. MySQL community server can be downloaded from mysql.net and it is free.
Combination of PHP ( scripting language ) and MySQL ( database server ) is the most popular in the world today among all web applications.
What is SQL
Sql is a common language to manage all the operations for a database. There are different SQL commands available to manage the database. You need not start reading or take training on all the commands at a time, you can use this site as a referance and read all our
free tutorials on SQL.
Now let us start with simple query to create table to store our student records. Then we will use insert query to add few records. Don't worry to understand all the meanings of the Query at this stage. Use this SQL to create the table.
CREATE TABLE student ( id int(2) NOT NULL auto_increment, name varchar(50) NOT NULL default '',
class varchar(10) NOT NULL default '', mark int(3) NOT NULL default '0',
UNIQUE KEY id (id) ) TYPE=MyISAM;
This will create the table for us. We can see that there are three fields in the
table. One is id which is an auto increment and will take one unique number each
time one record is added to the table. Next field is name of 50 length, this
will store the student name. Next is class field of 10 length.
Adding records
Let us fill the tables with some data. Here is the SQL to insert the data to the table. We
need not worry at this stage how this SQL works as we will discuss that in other
pages. You can just copy and paste this SQL code in your SQL window to
insert some records to the tables.
INSERT INTO student VALUES (1, 'John Deo', 'Four', 75);
INSERT INTO student VALUES (2, 'Max Ruin', 'Three', 85);
INSERT INTO student VALUES (3, 'Arnold', 'Three', 55);
INSERT INTO student VALUES (4, 'Krish Star', 'Four', 60);
INSERT INTO student VALUES (5, 'John Mike', 'Four', 60);
INSERT INTO student VALUES (6, 'Alex John', 'Five', 55);