Tutorial by Examples

Query to create table on db CREATE TABLE `user` ( `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(30) NOT NULL, `course` smallint(5) unsigned DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB; CREATE TABLE `course` ( `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT, `nam...

SELECT x, ... FROM ( SELECT y, ... FROM ... ) AS a JOIN tbl ON tbl.x = a.y WHERE ... This will evaluate the subquery into a temp table, then JOIN that to tbl. Prior to 5.6, there could not be an index on the temp table. So, this was potentially very inefficient: SELECT ... ...

This will get all the orders for all customers: SELECT c.CustomerName, o.OrderID FROM Customers AS c INNER JOIN Orders AS o ON c.CustomerID = o.CustomerID ORDER BY c.CustomerName, o.OrderID; This will count the number of orders for each customer: SELECT c.CustomerName, C...

MySQL does not support the FULL OUTER JOIN, but there are ways to emulate one. Setting up the data -- ---------------------------- -- Table structure for `owners` -- ---------------------------- DROP TABLE IF EXISTS `owners`; CREATE TABLE `owners` ( `owner_id` int(11) NOT NULL AUTO_INCREMENT,...

let's assume we have three table which can be used for simple website with Tags. Fist table is for Posts. Second for Tags Third for Tags & Post relation fist table "videogame" idtitlereg_dateContent1BioShock Infinite2016-08-08.... "tags" table idname1yennefer2eliza...

If you are a visually oriented person, this Venn diagram may help you understand the different types of JOINs that exist within MySQL.