1- #!/bin/ksh

operating system and shell type may cause different behaviour, this script is written and tested for Solaris and Korn Shell
 
2- if [ $# != 7 ] ..

Control for wrong argument count passed to the script from shell.

3- export CIGDEM_USERNAME1=$1 ..
export OH10=some-value ..

assign each argument into variables which will be used inside shell and sqlplus commands. Here $1 shows first parameter passed from shell to the script.

4- $OH10/bin/sqlplus -s > $CIGDEM_LOG_DIR/step1_$CIGDEM_DATE.log 2> $CIGDEM_LOG_DIR/step1_$CIGDEM_DATE.err <<EOF
$CIGDEM_USERNAME1/$CIGDEM_PASSWORD1@$OTNS10
@$CIGDEM_DIR/step1.sql $CIGDEM_EXP_DIR $CIGDEM_USERNAME3 $CIGDEM_PASSWORD3 $PERMANANT_TABLESPACE $TEMPORARY_TABLESPACE 
exit ;
EOF

this little one has a lot to say;
a. -s option for silent sqlplus not to press the SQL*Plus banner, prompts etc. into the logs, 
b. > and 2> options to redirect the outputs into files which may be needed for troubleshooting.
c. $CIGDEM_USERNAME1/$CIGDEM_PASSWORD1@$OTNS10 connecting this way lets you hide the password from the other os users, ps command only shows sqlplus.
d. @$CIGDEM_DIR/step1.sql $CIGDEM_EXP_DIR $CIGDEM_USERNAME3 $CIGDEM_PASSWORD3 $PERMANANT_TABLESPACE $TEMPORARY_TABLESPACE here we call step1.sql with arguments, they will be used with &n symbol inside sql statement.

5- inside the step1.sql; .. CREATE USER &2 IDENTIFIED by &3 TEMPORARY TABLESPACE &5 DEFAULT TABLESPACE &4 ; ..

here nothing new, just the arguments passed are used with & symbol.

6- retc=$?
if [[ $retc = 0 ]] 

to check if the last shell operation failed or not. if failed application exits.

7- $OH9/bin/exp $CIGDEM_USERNAME2 ..

typical export step, some performance options like direct and buffers are set, and since there is a potential to call this script from unix cron any path is also given in front of the binary called.

8- inside the step4.sql; .. SET HEADING OFF ECHO OFF FEEDBACK OFF ..
..
spool &1/step4_&2
SELECT ...
spool off   
...

this is the way to produce dynamic runnable sql scripts from Oracle dictionary, you spool the output and then you execute it.

9- inside the step4.sql; .. VARIABLE vgrantor varchar2(20);
BEGIN
     SELECT upper(to_char('&3')) INTO :vgrantor FROM DUAL;
	 dbms_output.put_line(:vgrantor);
END;
/
.. SELECT 'revoke ' || privilege || ' on ' || table_name || ' from ' || grantee || ' ;'
  FROM user_tab_privs p
 WHERE p.privilege NOT IN ('SELECT')
   AND p.grantor = :vgrantor ; ..
   
here we create a host variable from one argument passed from shell in order to use it in the where clause.   

---

here is the output of the test I have done and the os/db informations;

SP2D test@ctibcp:/export/home/test/cido # ls
clone_user.ksh  exp             log             step1.sql       step4.sql
SP2D test@ctibcp:/export/home/test/cido # ./clone_user.ksh osas_tyilmaz x adrref y adrref z 29112007
** User Drop OK ...
** 11/30/07 08:37:27

** Export OK ...
** 11/30/07 08:37:30

** Import OK ...
** 11/30/07 08:37:48

** Revoke Script OK ...
** 11/30/07 08:37:50

** Revoke OK ...
** 11/30/07 08:37:50


SP2D test@ctibcp:/export/home/test/cido # uname -a
SunOS ctibcp 5.10 Generic_125100-10 sun4u sparc SUNW,Sun-Fire-V890

SP2D test@ctibcp:/export/home/test/cido # sqlplus /nolog

SQL*Plus: Release 10.2.0.2.0 - Production on Thu Nov 29 17:03:45 2007

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