Understanding MySQL LEFT JOIN

MySQL CASE

MySQL LEFT JOIN allows you to get result set from two or more tables for certain matches.

Suppose you have two tables i.e. A and B. So if you join A to B using left join then all rows from the A tables will be displayed with matches a row from the B table.

Example of MySQL LEFT JOIN:

SELECT user.name, course.name FROM `user` LEFT JOIN `course` on user.course = course.id;

Here all rows from user tables will be displayed and only matches rows will be displayed from order table.

Read Also: Compare two tables in MySQL

Lets see below example:

`user` table –

idnamecourse
1A1
2B2
3C2
4D5
5E(NULL)

`course` table –

idname
1HTML
2CSS
3JavaScript
4PHP
5Ajax

So, the result will be:

user.namecourse.name
AHTML
BCSS
CCSS
DAjax
E(NULL)

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