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What Is Structured Query Language (SQL)?

This page explains how and why we use SQL to interact with databases.
Structured Query Language (SQL) is the most widely implemented database query language and is supported by many popular relational database systems, including: MS SQL Server, IBM DB2, MySQL, and Microsoft Access.

Since the late 1980s, SQL (pronounced ‘S Q L’ or ‘sequel’) has been a standard for both the International Organization for Standardization (ISO) and the American National Standards Institute (ANSI). Although SQL is considered a standard, database technology providers usually have their own SQL editor and there can be small variations in the syntax depending on how the SQL features are implemented.

SQLite3 implements a database engine and understands most of the standard SQL language. You can also check out the following pages for more information:

To help you learn SQL, we’ll present snippets of SQL. You’ll generally see examples of SQL presented like this:

CREATE TABLE Customers (
 CustomerID integer PRIMARY KEY AUTOINCREMENT,
 LastName varchar(255),
 FirstName varchar(255),
 DOB varchar(255),
 Mobile integer,
 CountryCode char(4) 
);

 

We’ll also show the output of any SQL or SQLite commands as follows

 

sqlite> SELECT * FROM Artist;
ArtistId Name 
---------- ----------
1 AC/DC 
2 Accept 
3 Aerosmith 
...

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