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Bog'liq Ma\'qola yanvar №9 engSQL capabilities. SQL(Structured Query Language) – This query language consists of many operators through which users and programs can access the database in Oracle(MBBT). Oracle utilities or various programs can perform database access without SQL operators, but it is impossible not to use this query language when executing queries.
In June 1970, EF Codd made his paper EF Codd, "A Relational Model of Data for Large Shared Data Banks" public. This article was published in Communications of the ACM. Nowadays, this model of Codd is accepted as the final model of "relational database management system (RMBBT)". IBM developed the SEQUEL (Structured English Query Language) language to implement Codd's model. This language was later changed to SQL, but is still referred to as a "sequel". 1979 Relational Software (now Oracle) Corporation released the first commercial development of SQL. Currently, SQL is the standard language of RMBBT.
The SQL language works in query-result form. Queries are issued not for each element, but for a whole group, and the result is obtained. For SQL, it doesn't matter what form or order the data in the database is, users
does not need to know the data. Only by writing the operators correctly will it be possible to extract the desired data.
SQL is the common standard language for all database management systems. It follows that if you learn this language once, you can work with any MBBT. A set of sql operators (small query program) created in one MBBT can be moved to any MBBT.
The following tasks can be performed using SQL statements:
Obtaining data by request.
Adding data to the rows of the table, deleting and updating the rows.
Create, modify and delete objects.
Set database and object permissions.
Create database users and ensure database security.
There are 2 types of SQL: interactive and built-in. These 2 types of SQL work the same but are used in different places.
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