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
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