SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd3cab533508934ca40127e2263df476a57941b1e1bcf13927b9d30feb8c4e64' 
  AND token = 'ppaTiPLJrIZTtyxZRJSGbvfRkiTXv5qVEmHiiicGPqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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