The SQL (Structured Query Language) is a type of programming language that helps to solve specific problems or problems related to the definition, manipulation and integrity of the information represented by the data stored in the databases. of data. in this article, we will try to explain all about related to SQL.
SQL (for its acronym in English Structured Query Language, in Spanish Structured Query Language ) is a domain-specific language used in programming designed to manage, and retrieve information management systems relational databases . 1 One of its main features is the use of algebra and relational calculus to carry out consultations in order to recover easily, information from databases and make changes to them.
Originally based on relational algebra and relational calculus, SQL consists of a data definition language, a data manipulation language and a data control language. The scope of SQL includes the insertion of data, queries, updates and deletion, the creation and modification of schemas and the control of access to data. Also, SQL is sometimes described as a declarative language, it also includes procedural elements.
SQL was one of the first commercial languages for the relational model of Edgar Frank Codd as described in his 1970 research paper The Relational Data Model for Large Shared Data Banks. Despite not fully adhering to the relational model described by Codd, it became the most widely used database language.
SQL became the standard of the American National Standards Institute (ANSI) in 1986 and of the International Organization for Standardization (ISO) in 1987. Since then, the standard has been revised to include more features. Despite the existence of both standards, most SQL codes are not completely portable between different database systems without adjustments.
History Of SQL Language
The origins of SQL are linked to the relational databases, specifically those that resided in IBM machines under the System R management system, developed by a group of IBM in San Jose, California.
In 1970, EF Codd proposes the relational model and associated with this a sublanguage of access to data based on the calculation of predicates. 2 Based on these ideas, the IBM laboratories defined the language SEQUEL (Structured English Query Language) that was later widely implemented by the system of database management (SGBD) experimental System R, developed in 1977 also by IBM. However, it was Oracle who introduced it for the first time in 1979 in a commercial product.
Why is it important to learn SQL?
- SQL simplifies your code: you do not have to think about writing complicated routines and with lots of lines of code to keep your information consistent.
- SQL will save you a lot: development time, quality in your code, effort and money that you would lose if, for example, you had to develop many routines that are already incorporated in the DBMS.
- Your application can run faster: once you have done all the tests required to verify that your code is optimal and works without problems, it may still be feasible to improve its performance many times with only a few small adjustments in your database.
- You can make your application independent of changes in the data.
- You remain in constant evolution but the SQL core changes very little: once you learn its operation you just have to concentrate on the subsequent innovations.
- Efficiency in solving problems: SQL has supported and adapted to changes for more than 30 years. Considering a large number of relational database systems that have arisen and represent almost 90 per cent of the total, the growth of the size of the databases, without a doubt it can be said that it is a very effective language.
- You can continue to work the relational databases with object-oriented programming in your preferred framework, as long as you implement the Object-Relational Mapping (ORM).
- It will also help you get a better understanding of the operation of the ORM.
- We hope that this article has helped you to clarify a little more your vision of what it means when in a project they ask you to use SQL. I invite you to continue learning more about the world of SQL with Style and thereby maintain and increase your enthusiasm in this fabulous area of knowledge.