SQL Quick Reference - W3Schools
SQL Statement Syntax; AND / OR: SELECT column_name(s) FROM table_name WHERE condition AND|OR condition: ALTER TABLE: ALTER TABLE table_name ADD column_name datatype. or. ALTER TABLE table_name DROP COLUMN column_name: AS (alias) SELECT column_name AS column_alias FROM table_name. or. SELECT column_name FROM table_name AS table_alias: BETWEEN ...
SQL Keywords Reference - W3Schools
Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.
SQL Tutorial - W3Schools
Our SQL tutorial will teach you how to use SQL in: MySQL, SQL Server, MS Access, Oracle, Sybase, Informix, Postgres, and other database systems. Start learning SQL now » Examples in Each Chapter
SQL Syntax - W3Schools
SQL Statements. Most of the actions you need to perform on a database are done with SQL statements. SQL statements consist of keywords that are easy to understand. The following SQL statement returns all records from a table named "Customers":
MySQL Functions - W3Schools
This reference contains string, numeric, date, and some advanced functions in MySQL.
Introduction to SQL - W3Schools
What is SQL? SQL stands for Structured Query Language; SQL lets you access and manipulate databases; SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987
MySQL SQL - W3Schools
Some of The Most Important SQL Commands. SELECT - extracts data from a database; UPDATE - updates data in a database; DELETE - deletes data from a database; INSERT INTO - inserts new data into a database; CREATE DATABASE - creates a new database; ALTER DATABASE - modifies a database; CREATE TABLE - creates a new table; ALTER TABLE - …
SQL FOREIGN KEY Constraint - W3Schools
SQL FOREIGN KEY Constraint The FOREIGN KEY constraint is used to prevent actions that would destroy links between tables. A FOREIGN KEY is a field (or collection of fields) in one table, that refers to the PRIMARY KEY in another table.
MySQL Tutorial - W3Schools
At W3Schools you will find a complete reference of MySQL data types and functions: MySQL Data Types. MySQL Functions
PostgreSQL Tutorial - W3Schools
In this tutorial you get a step by step guide on how to install and create a PostgreSQL database. You will learn how to create a project where you can create, read, update, and delete data. You will learn how to query, filter, and sort data from the database.