Oracle SQLPlus [Electronic resources] : The Definitive Guide, 2nd Edition نسخه متنی

14.4 Windows GUI SQL*Plus

The Windows GUI version of
SQL*Plus implements an
Environment
dialog from which you can specify values for many of the options you
would otherwise control via the SET command. Two environment options
are unique to Windows GUI SQL*Plus. To get to this
Environment dialog, run the Windows GUI version
of SQL*Plus and select the Options Environment menu option. You'll see the
dialog in Figure 14-2.

The left half of the dialog in Figure 14-2 provides
a cumbersome alternative to using the SET command. For example,
rather than issue SET LINESIZE 132, you can open this dialog, scroll
down in the list of Set Options to linesize, click the
Custom radio-button, and type the value 132 into
the text box below the On and
Off radio buttons. Believe me,
you'll find it easier to use the SET command.

The right half of the dialog however, provides two options unique to
the Windows GUI version of SQL*Plus. Buffer Length represents the
number of lines of scrollback history that SQL*Plus maintains. If
you're bringing back large amounts of query results
that you'd like to scroll through, you may find it
helpful to bump up the Buffer Length to a higher value. At least,
I've often used that ability.

Buffer Width represents the left-to-right width of the SQL*Plus
window. If you increase LINESIZE above 100, you'll
find that Buffer Width is automatically increased to match, so you
don't need to worry about manually specifying a
value. The only reason to specify a value manually for Buffer Width
is if you want to free up memory by reducing it. Probably due to the
generous amounts of memory in most modern computers,
I've never found memory consumption by the SQL*Plus
screen buffer to be anything worth being concerned about.

Changes to Buffer Width and Buffer Length persist from one run of SQL*Plus to the next. Set the SQL*Plus Buffer Length to, say, 5000, and it will be 5000 each time you run the Windows GUI version. However, Set Options that you specify from the Environment dialog in Figure 14-1 are valid only for the one instance of SQL*Plus that you are running. When you next start SQL*Plus, all Set Options will return to their defaults.