To undo all column formatting, the command is:
CLEAR COLUMNS
A script is a text file that is stored in the operating system in the C:/Oracle .../bin directory (Windows) and run with a START command.
In the text file, we can include the COLUMN format, the statement, and then a CLEAR COLUMNS command.
As an example, suppose we have such a script called myscript.txt and it contains the following:
COLUMN orig_salary FORMAT $990.99 SELECT empno, ename, orig_salary, -- from ww w.j a v a 2s . c om curr_salary FROM employee; CLEAR COLUMNS
This script presupposes nothing about the formatting of orig_salary, and after it is run, the formatting is not persistent.
The script is executed like this:
START myscript.txt
or
@myscript.txt
from the SQL> command line.