Selecting columns

Suppose you need emp_no and dept_no from dept_manager:

mysql> SELECT emp_no, dept_no FROM dept_manager;
+--------+---------+
| emp_no | dept_no |
+--------+---------+
| 110022 | d001    |
| 110039 | d001    |
| 110085 | d002    |
| 110114 | d002    |
| 110183 | d003    |
| 110228 | d003    |
| 110303 | d004    |
| 110344 | d004    |
| 110386 | d004    |
| 110420 | d004    |
| 110511 | d005    |
| 110567 | d005    |
| 110725 | d006    |
| 110765 | d006    |
| 110800 | d006    |
| 110854 | d006    |
| 111035 | d007    |
| 111133 | d007    |
| 111400 | d008    |
| 111534 | d008    |
| 111692 | d009    |
| 111784 | d009    |
| 111877 | d009    |
| 111939 | d009    |
+--------+---------+
24 rows in set (0.00 sec)