Summary

In this unit we have presented the language used sentences ANSI / ISO SQL92 definition, manipulation and control of relational databases. As we mentioned in the introduction, the SQL is a very powerful language, and this means that there are more statements and options that we have explained in this module. However, the fact remains that we have seen many statements that some relational systems currently offered. We tried to follow as closely as standard, including comments only when in most commercial relational systems did some operation differently.

Knowing we can work co SQL92n any commercial relational system, we'll just spend a few hours to see what changes occur with respect to the standard.

Remember how it will create a SQL database:

1) First, we must give names to the database with the CREATE DATABASE, if any, or CREATE SCHEMA.

2) Then define the tables, domains, assertions and views that form our database.

3) After defining the tables, which are completely empty, they must complete with the INSERT INTO.

When the database has a set of rows, lto be able to manipulate, either updating rows or doing consultations.

In addition, we use all the control statements that we have explained.