SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '425ee786a36ff8b95ee14056db52f87efaab7c3de5ca438063d013022d0e158a' 
  AND token = 'nfJFjX6o37LcIWmlKu+0QJyAfopuKOlLiWZbZeOTNec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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