SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '127be5dc683d467f0d81601e8d665a95baa214355ab1598e68cd1e78f65a2723' 
  AND token = 'L9sqWw+nMCGMhvifxhk+GxW+6LeXAO6qk4CACfxA8KE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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