What is SQL

SQL stands for Structured Query Language. It's a programming language used to manage and manipulate databases. SQL is mainly used for querying and operating on data stored in Relational Database Management Systems (RDBMS), or for stream processing in a Relational Data Stream Management System (RDSMS).

Key uses of SQL include:

1. Querying Data: This is the most common operation. SQL's SELECT statements are used to fetch data from a database. You can fetch all columns, a selection of columns, a single row, multiple rows, a portion of a row, and so on, depending on the query's conditions.

2. Updating Data: SQL allows you to update existing data in a database using the UPDATE statement.

3. Inserting Data: You can add new data into a database using SQL's INSERT statement.

4. Deleting Data: SQL allows you to remove data from a database with the DELETE statement.

5. Creating, Altering, and Dropping Tables: SQL provides statements to create new tables (CREATE), change existing tables (ALTER), or remove existing tables (DROP).

6. Creating, Altering, and Dropping Databases: Similar to tables, SQL can also be used to create new databases, change existing databases, or remove existing databases.

7. Creating Views: A view is a tailored presentation of the data contained in one or more tables (or other views). Views don't store data themselves but display data stored in underlying tables. They are created using the CREATE VIEW statement.

8. Data Control: SQL has commands to control access to the data and databases, providing security mechanisms.

SQL is a standard language for managing data held in RDBMS or for stream processing in RDSMS, and it is very important in the world of data, where retrieving, updating, or deleting data efficiently is crucial.

Although SQL is an ANSI (American National Standards Institute) standard, there are different versions of the SQL language. However, to be in compliance with the ANSI standard, they all support at least the major commands such as SELECT, UPDATE, DELETE, INSERT, WHERE in a similar manner.