First create a my.cnf file like this

[mysqldump]
user=
password=

Then create the following script

#!/bin/bash
# Shell script to backup MySQL database

CONFIG="/home2/examdevo/dailyBackup/my.cnf"
DEST="/home2/examdevo/dailyBackup"

# How many days old files must be to be removed
DAYS=3

MYSQL="$(which mysql)"
MYSQLDUMP="$(which mysqldump)"
GZIP="$(which gzip)"

# Get date in dd-mm-yyyy format
NOW="$(date +"%d-%m-%Y_%s")"

# Create Backup sub-directories
MBD="$DEST/$NOW/mysql"
install -d $MBD

# DB skip list
SKIP="information_schema
another_one_db"

# Get all databases
DBS="examdevo_germinate"

# Archive database dumps
for db in $DBS
do
    skipdb=-1
    if [ "$SKIP" != "" ];
    then
                for i in $SKIP
                do
                        [ "$db" == "$i" ] && skipdb=1 || :
                done
    fi

    if [ "$skipdb" == "-1" ] ; then
        FILE="$MBD/$db.sql"
        $MYSQLDUMP --defaults-extra-file=$CONFIG $db > $FILE
    fi
done

# Archive the directory, send mail and cleanup
cd $DEST
tar -cf $NOW.tar $NOW
$GZIP -9 $NOW.tar

rm -rf $NOW

# Remove old files
find $DEST -mtime +$DAYS -exec rm -f {} \;