DEL, EXISTS, KEYS & TYPE

These commands work on keys regardless of their data type.

Commands

• DEL key [key ...] — delete keys, return count deleted
• EXISTS key [key ...] — return count of keys that exist
• KEYS * — return all keys as array (we only support * wildcard)
• TYPE key — return type: +string, +list, +hash, +set, +zset, or +none
• RENAME key newkey — rename key, error if source doesn't exist

DEL Is Universal

DEL removes a key regardless of its type — string, list, hash, set, or sorted set. It cleans up all associated data.

TYPE Returns Simple Strings

Note: TYPE returns a simple string (+string\r\n), not a bulk string. This is one of the few Redis commands with this behavior.

EXISTS Counting

EXISTS a a b returns :3 if all exist — it counts each argument, even duplicates. This is useful for checking multiple keys at once.