Basic bash script Example: input parameters validation, get run_date, replace sting in a file, backup original file.

===========================
General
===========================
This script does search and remove a string inside a file.

===========================
Code
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my_user@my_server:~/scripts>% less remove_table_from_rep.sh 

#!/bin/bash
echo
echo $0 Starting...........................
echo


#----------------------------
#Validate Input Parameters
#----------------------------
PARAM_NUMBER=$#
echo Input Parameters Number: $PARAM_NUMBER
if [[ $PARAM_NUMBER -ne 3 ]]; then
  echo "Usage $0 FOLDER_NAME FILE_NAME TABLE_NAME"
  exit 0
fi

FOLDER_NAME=$1
FILE_NAME=$2
TABLE_NAME=$3

BACKUP_FOLDER=/some/path/scripts/backup_ogg_param
RUN_DATE=`date +"%Y%m%d_%H%M%S"`

#----------------------------
#Replace String
#----------------------------

grep -v ${TABLE_NAME} ${FOLDER_NAME}/${FILE_NAME} > ${FOLDER_NAME}/${FILE_NAME}_bak

cp ${FOLDER_NAME}/${FILE_NAME} ${BACKUP_FOLDER}/${FILE_NAME}_${RUN_DATE}
mv ${FOLDER_NAME}/${FILE_NAME}_bak ${FOLDER_NAME}/${FILE_NAME}

echo 
echo File ${FOLDER_NAME}/${FILE_NAME} was copied to  ${BACKUP_FOLDER}/${FILE_NAME}_${RUN_DATE}
echo $0 Finished...........................
echo