Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c515dacd724abb33793c5f94a0c88c97d5d9c2498f2deb48ca5a551dfe239e10' 
  AND token = 'IAYcUlGptgPzfn97YcnWAf3ymT+UAiCo8lrk/2MCLO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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