When querying, you can take an alias for the table and the field. This alias can be substituted for its specified table and field
Alias a table
Mysql> SELECT * fromDepartment D - WHEREd.d_id=1001;+------+-----------+--------------+-------------+|d_id|D_name| function |Address|+------+-----------+--------------+-------------+| 1001 |Department of Science and Technology|Product development|Building 3rd, Level 5|+------+-----------+--------------+-------------+Rowinch Set(0.00Sec
Here is an alias of D for the Department table.
Alias a field
Mysql> SELECTd_id asDEPARTMENT_ID, D_name asDepartment_name - fromDepartment;+---------------+-----------------+|department_id|Department_name|+---------------+-----------------+| 1001 |Department of Science and Technology|| 1002 |Production department|| 1003 |Sales Department|+---------------+-----------------+Rowsinch Set(0.00Sec
The syntax here is similar to the above, except that it is added as
How to use Mysql aliases