SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45e74ac22a6ce494130f9b23be841fa7d5e7486b140327c5b0dc0dc708b45f9b' 
  AND token = 'qp4JnyXqurnre5w0IzV55VEytwGKGnkCSMCYsatxIyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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