SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '027046261315fbaa64613e771f56b7065552e7aa308cecc49a92f76db0e33fef' 
  AND token = 'v1KvpxUqU8gTTZs9ZudOOu0GujQHfiqp8KyRc5Zrwh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}