SQL "for teapots": what do you need to know for beginners?

To date, SQL courses "for teapots" are becoming more popular. This can be very simply explained, because in the modern world, you can often find so-called "dynamic" web services. They are quite flexible and based on databases. All the beginning programmers who decided to devote themselves to the creation of sites, first of all, are registered for the SQL courses "for teapots".

Why study this language?

First of all, SQL is being taught to further create a wide variety of applications for one of the most popular blog engines today - WordPress. After going through a few simple lessons, you can already create queries of any complexity, which only confirms the simplicity of this language.

What is SQL?

Structured Query Language, or the language of structured queries, was created for one single purpose: to determine the type of data, to provide access to them and to process them in fairly short periods of time. If you know the SQL-value, then you will understand that this server is referred to the so-called "non-procedural" languages. That is, in its ability is only a description of any components or results that you want to see in the future on the site. But at the same time the programmer does not indicate what exactly results are going to be obtained. Each new request in this language is, as it were, an additional "superstructure." It is in this order in which they are entered in the database that requests will be executed.

What procedures can be performed with this language?

Despite its simplicity, the SQL database allows you to create quite a lot of various queries. So what can you do if you learn this important language in programming?

• Create a wide variety of tables;
• Receive, store and modify received data;
• Change the structure of the tables at your discretion;
• Combine the information received into single blocks;
• Calculate the received data;
• To ensure full protection of information.

Which teams are the most popular in this language?

If you decide to attend SQL courses for Dummies, then you will get detailed information about the commands that are used to create queries with it. The most common today are:

1. DDL is the command that defines the data. It is used to create, modify and delete a wide variety of objects in the database.
2. DCL is the command that manages data. It is used to give different users access to information in the database, and also to use tables or views.
3. TCL is a command that manages a variety of transactions. Its main purpose is to determine the progress of the transaction.
4. DML - manipulates the received data. Its task is to allow the user to move various information from the database or make it there.

The types of privileges that exist in this server

Privileges are those actions that a user can perform in accordance with his status. The most minimal, of course, is the usual login to the system. Of course, over time privileges can change. Old ones will be deleted, and new ones will be added. To date, all those who take SQL Server courses for Dummies know that there are several types of allowed actions:

1. Object type - the user is allowed to execute a command only with respect to a certain object that is in the database. The privileges for different objects are different. They also bind not only to a particular user, but also to tables. If someone, using his capabilities, created a table, then he is considered its owner. Therefore, it is his right to assign new privileges to other users related to the information in it.
2. The system type is the so-called copyrights to the data. Users who have received such privileges can create different objects in the database.

History of SQL creation

This language was created by the IBM research lab in 1970. At that time his name was somewhat different (SEQUEL), but after several years of use it was changed, slightly reducing. Despite this, even today many well-known world experts in programming still pronounce the name in the old-fashioned way. SQL was created with the sole purpose of inventing a language that would be so simple that even ordinary Internet users could learn it without too much trouble. An interesting fact is that at the time SQL was not the only such language. In California, another group of specialists developed a similar Ingres, but it never became widespread. Until 1980, there were several variations of SQL, which were only slightly different from each other. To prevent confusion, in 1983, he created a standard version of it, which is popular today. The SQL "for Dummies" courses allow you to learn a lot more about the service and fully study it in a few weeks.