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 –
| id | name | course |
|---|---|---|
| 1 | A | 1 |
| 2 | B | 2 |
| 3 | C | 2 |
| 4 | D | 5 |
| 5 | E | (NULL) |
`course` table –
| id | name |
|---|---|
| 1 | HTML |
| 2 | CSS |
| 3 | JavaScript |
| 4 | PHP |
| 5 | Ajax |
So, the result will be:
| user.name | course.name |
|---|---|
| A | HTML |
| B | CSS |
| C | CSS |
| D | Ajax |
| E | (NULL) |
