SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '034ddd00f41d612fa30247b6249fd0c6a5b965524ecafc0ea1272c782767a325' 
  AND token = '3gNZosP4NXxGYnVFdGZ/kH7UlxLk5H5UVqow4CWBp1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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