SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = 'e6bc9d08d58e830ff0ee1d4fd8908c93480469e816229c66141c1579cc55973c' 
  AND token = 'KRGBr+r7m6uIzVxkwBIAumxruIXjMCiB8YDBR+JtZJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}