Oracle 12.2 – SQL*Plus Command History

Currently I am preparing some slides for future events. I will share some of the topics beforehand. First topic is the one mentioned in the title, with Oracle Database 12.2 we finally get a command history. Though only a tiny new bit this is one of my favorite new features.
Let’s see how this works.

$ sqlplus / as sysdba

SQL*Plus: Release 12.2.0.1.0 Production on Mon May 8 09:49:04 2017

Copyright (c) 1982, 2016, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

SQL> history
SP2-1650: History is off, use "SET HIST[ORY] ON" to enable History.

Ok, the feature is inactive by default. We need to enable it by setting it to “ON” or to a number specifying how many statements should be kept in the history.

SQL> set history 50

SQL> select * from dual;
D
-
X
SQL> history
  1  select * from dual;

Let’s see what else is possible with the “history” command:

SQL> help history

 HISTORY
 -------

 Stores, lists, executes, edits of the commands
 entered during the current SQL*Plus session.

 HIST[ORY] [N {RUN | EDIT | DEL[ETE]}] | [CLEAR]

 N is the entry number listed in the history list.
 Use this number to recall, edit or delete the command.

 Example:
 HIST 3 RUN - will run the 3rd entry from the list.

 HIST[ORY] without any option will list all entries in the list.

We can easily run any command by specifying the number from the history or remove a command from the history.

SQL> hist
  1  select * from dual;
  2  select count(*) from dba_objects where status <> 'VALID';

SQL> hist 2 run

  COUNT(*)
----------
         0

SQL> hist 1 del
SQL> hist
  1  select count(*) from dba_objects where status <> 'VALID';

And by the way, the history runs at statement level, not at line level. So this is maybe the most important advantage over OS level command history using arrow-up and arrow-down (natively on Windows or with “rlwrap” on Linux).

SQL> select count(*) from dba_users
  2  where oracle_maintained = 'Y'
  3  and account_status = 'OPEN';

  COUNT(*)
----------
         2

SQL> hist
  1  select count(*) from dba_objects where status <> 'VALID';
  2  select count(*) from dba_users
     where oracle_maintained = 'Y'
     and account_status = 'OPEN';

SQL> hist 2 run

  COUNT(*)
----------
         2

Enjoy the new feature.