Oracle Database 12c Release 2 - SQL*Plus History Command

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As you know that we can repeat our previous SQL*Plus commands in Windows CMD. But in UNIX based systems not supported command line history of SQL*PLus.  For this reason in UNIX and Linux, we used rlwrap utility to see the SQL*Plus command line history and quickly recall previous SQL*Plus commands.

With seconds release of Oracle Database 12c coming SQL*Plus history command for the history of the command line in Linux.

I want to share some example for this command:

Before using History we must enable history command as below:

SQL> set history on

The syntax of HISTORY command as bellow

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.


As you seen from syntax, we can edit, delete, clear list items in history.

SQL> set history on 
SQL> 
SQL> 
SQL> select name from v$database;

NAME
---------
DB122

SQL> select name, database_role from v$database;

NAME   DATABASE_ROLE
--------- ----------------
DB122   PRIMARY

SQL> 
SQL> select banner from v$version; 

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
PL/SQL Release 12.2.0.1.0 - Production
CORE 12.2.0.1.0 Production
TNS for Linux: Version 12.2.0.1.0 - Production
NLSRTL Version 12.2.0.1.0 - Production

SQL> 
SQL> 
SQL> hist list
  1  select name from v$database;
  2  select name, database_role from v$database;
  3  select banner from v$version;

SQL> 
SQL> 
SQL> hist 1 run

NAME
---------
DB122

SQL> hist 3 run

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
PL/SQL Release 12.2.0.1.0 - Production
CORE 12.2.0.1.0 Production
TNS for Linux: Version 12.2.0.1.0 - Production
NLSRTL Version 12.2.0.1.0 - Production

SQL> 
SQL> 
SQL> hist clear
SQL> 
SQL> hist list
SP2-1651: History list is empty.
SQL> 
SQL> 
SQL> select name from v$database;

NAME
---------
DB122

SQL> select banner from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
PL/SQL Release 12.2.0.1.0 - Production
CORE 12.2.0.1.0 Production
TNS for Linux: Version 12.2.0.1.0 - Production
NLSRTL Version 12.2.0.1.0 - Production

SQL> select instance_name from v$instance;

INSTANCE_NAME
----------------
db122

SQL> 
SQL> 
SQL> hist list
  1  select name from v$database;
  2  select banner from v$version;
  3  select instance_name from v$instance;

SQL> 
SQL> 
SQL> hist 2 edit

Oracle SQL*Plus using vi editor for editing of history command line.



SQL> 
SQL> hist list
  1  select name from v$database;
  2  select banner from v$version;
  3  select instance_name from v$instance;
  4  select banner from v$version
     where rownum <=1;


SQL> hist 4 run 

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

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


Please watch for a video tutorial on Youtube:



Best Regards
Mahir M. Quluzade

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