SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd014322ffeac9877d47caf5c61b0f06b17debe244c1e1080819a4a3bd2d356b8' 
  AND token = 'Q1T6BDEEbWB4Bzg8NNk5VxhA9OE/VMyGKYHH2LmZkG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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