SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd43003170fdad9ae52ae53f0555066b2b4e1383fca8131ad0d050685c3082777' 
  AND token = 'wTS23qhGjnMspB/CuUWB98b0S9NjFHYwgXQ6JkTc6qI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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