how to passing variable from bash to sqlplus

Question

I have below code in bash:

#/!bin/bash


USERS=tom1,tom2,tom3

and I want to drop all users from my variable "USERS" via sqlplus

#/!bin/bash

USERS=tom1,tom2,tom3

sqlplus -s system/*** <<EOF
*some code*
DROP USER tom1 CASCADE;
DROP USER tom2 CASCADE;
DROP USER tom2 CASCADE;
EOF

pls help

Answer 1

Splitting in database using sql / plsql by using the USERS variable is complex and requires understanding of REGEXP functions and I will not recommend that to you. Moreover, it would also require Dynamic Sql to execute a drop query.

I would suggest you to split it within the shell script,create a script and execute it in sqlplus

USERS="tom1,tom2,tom3"
    echo ${USERS} | tr ',' '\n' | while read word; do
        echo "drop user $word;"
    done >drop_users.sql

sqlplus -s system/pwd <<EOF
#some code
@drop_users.sql
EOF

Answer 2

Your code is OK except for DDL commands for Oracle DB which are derived from USERS parameter of the script file, call userDrop.sh . To make suitable relation with USERS parameter and DB , an extra file ( drpUsr.sql ) should be produced, and invoked inside EOF tags with an @ sign prefixing.

Let's edit by vi command :

$ vi userDrop.sh

#!/bin/bash
USERS=tom1,tom2,tom3

IFS=',' read -ra usr <<< "$USERS" #--here IFS(internal field separator) is ','
for i in "${usr[@]}"; do
  echo "drop user "$i" cascade;"
done > drpUsr.sql

#--to drop a user a privileged user sys or system needed.    
sqlplus / as sysdba <<EOF
@drpUsr.sql;
exit;
EOF

Call as

$ . userDrop.sh

and do not forget to come back to command prompt by an exit command of DB.