Controls the size of the editing buffer that you create when you
    use the EDIT statement with a wildcard as the argument.

    o  SET EDIT KEEP n

       Tells SQL to save the previous n statements. For example,
       assume you have specified SET EDIT KEEP 5. When you type EDIT
       *, SQL places the previous five statements in the editing
       buffer. The number you specify with SET EDIT KEEP is the
       maximum number of statements you can recall with the EDIT
       statement. The default is 20.

    o  SET EDIT NOKEEP

       This statement is equivalent to SET EDIT KEEP 0. If you use
       this form of the statement and you type EDIT or EDIT *, your
       editing buffer will be empty. This form of the statement saves
       system resources when you are running command files rather
       than an interactive process.

    o  SET EDIT PURGE

       This statement retains the value of the KEEP parameter but
       purges all previous statements. As with SET EDIT NOKEEP, if
       you use the SET EDIT PURGE statement and then EDIT or EDIT *,
       your editing buffer will be empty. Unlike the SET EDIT NOKEEP
       statement, however, SET EDIT PURGE causes SQL to accumulate
       subsequent statements to place in the editing buffer when you
       issue EDIT statements later in the interactive session.