SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fa0d7683649c3fb91a9453dedb4bcc206f64e4cc99b01f0bf24295a166f8141' 
  AND token = 'ZSgV3ikUU6ZCqe5ldzYFzq/sZN6vYRyMHu1B3mn2F5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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