sqlplus tips

Tricks and tips about your everyday Oracle sqlplus usage.

Oracle
SQL

After I tryed psql, I hate sqlplus.

Hey Oracle, you are a really big corporation. Why do you keep sqlplus so unusable? Don’t you have money to pay your developers and add new features like command history?

RANT> exit

By the way, sometimes I need to use sqlplus. Here it is a set of tips I always forget.

How to login

 $ sqlplus [email protected]

where schema is your user name and sid can be found in the tnsnames.ora.

Do not show your password around, avoid this syntax

 $ sqlplus schema/[email protected]

You can also do this

$ sqlplus /nolog
SQL> CONNECT AS SYSDBA -- if you can :)

Check your environment

Make sure your env vars are set properly

$ echo $ORACLE_HOME

Set your EDITOR var to enable the EDIT command. It is a good idea to set this variable in your .bash_profile, cause it is used also by other softwares (like git, subversion, PostgreSQL and many more)

$ export EDITOR=vim

If you are already logged in sqlplus, you can do

SQL> DEFINE _EDITOR=vim

Exit command

SQL> quit

Basic operations

Manage SQL buffer content

Suppose you run a query, for instance

SQL> SELECT SYSDATE FROM DUAL;

SYSDATE
------------------
02-APR-15

Now the SQL buffer contains last statement, you can run it again with

SQL> RUN

Or even, the more comfortable

SQL> r

Yes, because Oracle is not case sensitive with its keywords and many sqlplus commands has a shorter alias, for example LIST has L or l.

If you want to show the most recently executed SQL command

SQL> LIST

or simply

SQL> l

Show command help

SQL> HELP INDEX

Enter Help [topic] for help.

 @             COPY         PAUSE                    SHUTDOWN
 @@            DEFINE       PRINT                    SPOOL
 /             DEL          PROMPT                   SQLPLUS
 ACCEPT        DESCRIBE     QUIT                     START
 APPEND        DISCONNECT   RECOVER                  STARTUP
 ARCHIVE LOG   EDIT         REMARK                   STORE
 ATTRIBUTE     EXECUTE      REPFOOTER                TIMING
 BREAK         EXIT         REPHEADER                TTITLE
 BTITLE        GET          RESERVED WORDS (SQL)     UNDEFINE
 CHANGE        HELP         RESERVED WORDS (PL/SQL)  VARIABLE
 CLEAR         HOST         RUN                      WHENEVER OSERROR
 COLUMN        INPUT        SAVE                     WHENEVER SQLERROR
 COMPUTE       LIST         SET                      XQUERY
 CONNECT       PASSWORD     SHOW

For example

SQL> HELP LIST

Show sqlplus settings

SQL> SHOW ALL

Show current user

SQL> SHOW USER

Get tables list

SQL> SELECT * FROM user_objects WHERE object_type = 'TABLE';

List table columns

SQL> DESC mytable

Common tasks

Get first n rows from a table

SQL> SELECT * FROM foo WHERE ROWNUM < 100;

Setup your prompt

Defaults are really weird, try to make it more usable.

Create a login.sql file in your current directory, your $HOME for instance, or in some directory you add to SQLPATH env var. Add to login.sql the following content

-- Make SQL prompt show database name so I know where I am (thanks to Tom Kyte for this)
COLUMN global_name new_value gname
SET TERMOUT OFF
SELECT LOWER(USER) || '@' || global_name || '> ' AS global_name FROM global_name;
SET SQLPROMPT '&gname'
SET TERMOUT ON

SET TIME ON
SET PAUSE ON
SET PAGESIZE 80
SET LINESIZE 120

Remember that, since PAUSE flag is on, you should hit enter after you run a query to see a first result.

Compute table size

SQL> SELECT segment_name, bytes/(1024*1024) AS Mb FROM user_segments WHERE segment_type = 'TABLE' ORDER BY 2 DESC;

Spool table content to file

#!/bin/bash
#
## Configuration
#
# Don't forget to edit credentials, filename and query, see below.
#
## How to launch
#
#    $ chmod +x spool_Oracle_table.sh
#    $ nohup spool_Oracle_table.sh > spool_Oracle_table.nohup &
###

sqlplus -S /nolog <<EOF > /dev/null
-------------------------------------------
-- Set your credentials here
-------------------------------------------
CONN Oracle_user/[email protected]_sid
-------------------------------------------
SET ARRAY 100
SET PAGES 0
SET WRAP OFF
SET FLUSH OFF
SET FEED OFF
SET FEEDBACK OFF
SET ECHO OFF
SET VERIFY OFF
SET TERM OFF
SET TRIMSPOOL ON
SET HEAD OFF
SET TRIM ON
SET COLSEP "|"
SET LINESIZE 800 --> this value should be enough otherwise rows will be truncated
--------------------------------------------------------------------
-- edit you filename here
SPOOL filename.dat
--------------------------------------------------------------------
-- your spool query here, something like
-- SELECT
--   col1
--   || '|' || col2
--   || '|' || TRIM(col3_varchar)
--   || '|' || TO_CHAR(col3_date, 'yyyy-mm-dd')
-- FROM table;
SPOOL OFF
EXIT
EOF

Edit SQL buffer

Suppose you write a wrong query and you want to fix it.

SQL> SELECT
  2  sydate
  3  FROM DUAL;
SYDATE
*
*ERROR at line 2:
ORA-00904: "SYDATE": invalid identifier

Go to line 2

SQL> 2
  2* sydate

Apply a substitution

SQL> c/sydate/SYSDATE/
  2* sysdate

Run the query

SQL> r
  1  SELECT
  2  SYSDATE
  3* FROM DUAL

SYSDATE
------------------
02-APR-15

Format query output

If you try the following query without formatting output, you will get something unreadable.

SQL> SELECT * FROM NLS_DATABASE_PARAMETERS;

Try this

SQL> SET LINES 200
SQL> COL parameter FOR a25
SQL> COL name FOR a50

Then run it again

SQL> r

Note that 25 is enough for parameter field, in fact

SQL> SELECT MAX(LENGTH(parameter)) len FROM NLS_DATABASE_PARAMETERS;

       LEN
----------
        23

Generate SQL

Sometimes it is really useful to launch a SQL that generates a SQL statement. For example in the example Format query output you can run.

SQL> SELECT 'COL parameter FOR a' || MAX(LENGTH(parameter)) copyme FROM NLS_DATABASE_PARAMETERS;

COPYME
--------------------------------------------------------------------------------
COL parameter FOR a23

to generate the COL parameter FOR a23 expression, and then just copy and paste it into your SQL prompt.

Launch a script

SQL> @script.sql

if script.sql is in the same directory you launched sqlplus.

You can pass an absolute path

SQL> @/path/to/script.sql

and even a name with spaces, by adding double quotes

SQL> @"001 - My script.sql"

Note that if there is an ampersand (&) you will be prompted to insert a value, since it is the syntax for interactive variable assignations. Unluckly, if there is any string in your insert that contains an ampersand, sqlplus will recognize it as a variable, so you will be prompted for its assignation. You can solve it by setting

SET DEFINE OFF

in your script or in the sqlplus session.

See also