五、为了安全要求每次执行shell都手工输入密码$ vi test5.sh#!/bin/bashecho -n "Enter password for u_test:"read PASSWDsqlplus -S /nolog <<EOFconn u_test/$PASSWDselect * from tab;exitEOF$ chmod +x test5.sh$ ./test5.sh六、为了安全从文件读取密码对密码文件设置权限, 只有用户自己才能读写.$ echo 'iamwangnc' > u_test.txt$ chmod g-rwx,o-rwx u_test.txt$ vi test6.sh#!/bin/bashPASSWD=`cat u_test.txt`sqlplus -S /nolog <<EOFconn u_test/$PASSWDselect * from tab;exitEOF$ chmod +x test6.sh$ ./test6.sh