mysql_dump_all_db.sh

#!/bin/sh

set -eu

SELECT_SCHEMA_SQL=<<EOF
SELECT SCHEMA_NAME FROM information_schema.SCHEMATA
WHERE SCHEMA_NAME NOT IN ("information_schema", "performance_schema");
EOF

mysql -u root -N -e "${SELECT_SCHEMA_SQL}" | while read dbname; do
  echo "Dumping database $dbname"
  time mysqldump -u root --single-transaction --databases $dbname | gzip -c >| "${dbname}.sql.gz";
  echo "Done."
done