1. backup:
cd /backup
mkdir -p adir
chmod 1777 adir
mysqldump -Ffe db_name table_name --skip-add-locks --where="where_clause" --tab="adir"

2. restore:
cd /backup
mkdir -p adir
chmod 1777 adir
mysql -e "SET GLOBAL local_infile = 1"
mysqlimport --use-threads=8 -fik -v --local db_name table_name.txt