Renamed to sqlinjection

src/main/resources/lessons/sqlinjection/documentation/SqlInjection_introduction_content3.adoc

@@ -0,0 +1,24 @@
+=== Data Definition Language (DDL)
+
+Data definition language includes commands for defining data structures. DDL commands are commonly used to define a database's schema. The schema refers to the overall structure or organization of the database and. in SQL databases, includes objects such as tables, indexes, views, relationships, triggers, and more.
+
+If an attacker successfully "injects" DDL type SQL commands into a database, he can violate the integrity (using ALTER and DROP statements) and availability (using DROP statements) of a system.
+
+
+* DDL commands are used for creating, modifying, and dropping the structure of database objects.
+* CREATE - create database objects such as tables and views
+* ALTER - alters the structure of the existing database
+* DROP - delete objects from the database
+* Example:
+** CREATE TABLE employees( +
+       userid varchar(6) not null primary key, +
+       first_name varchar(20), +
+       last_name varchar(20), +
+       department varchar(20), +
+       salary varchar(10), +
+       auth_tan varchar(6) +
+);
+** This statement creates the employees example table given on page 2.
+
+Now try to modify the schema by adding the column "phone" (varchar(20)) to the table "employees". :
+