INPUT N° 2 GROUP C FILE: 891434

DDL (Data Definition Lenguaje )

Simple artificial lenguaje, serves to define and describe the objects in the database, structure, relations and constraints. Some examples of functions: creation, modification and deletion of tables that make up the database.

1. Create table: is used to create new tables in the database
Example:
 
CREATE TABLE Persons

(

PersonID int,

LastName varchar (255),

FirstName varchar(255),

Address varchar(255),

City varchar(255)

);

2. Drop table: is used to delete tables in the database
Example:

DROP TABLE Persons

3. Alter table: is used to modify the tables of the database, adding fields or changing the definition of fields
Example:

ALTER TABLE Persons

ADD column_name datatype




Prepared by:
María Paula Herrera López