Inner the difference between join, left JOIN, right join, and full join

Test table:

EMP Table Sal Table

Left JOIN: Results All rows are displayed in the table, and the right table determines that the column is the same as the left.

SELECT * FROM EMP left join SAL on EMP. ename = SAL.  ename;

Right join: Results All rows are displayed in the table on the left, the table on the right is consistent with the table

Select * from EMP right join SAL on EMP. ename = SAL.  ename;

INNER JOIN: The left and right table to determine the consistency of data;

SELECT * FROM EMP inner join SAL on EMP. ename = SAL.  ename;

Full join: All rows of the table are left and right, and the table is judged in the same row, inconsistent with a single line.

SELECT * from EMP full join SAL on EMP. ename = SAL.  ename;

Inner the difference between join, left JOIN, right join, and full join