SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5baa7ce99c865cf52f34d5613c5efaa7cb8c61dd06b8d560a6bf6892806c96af' 
  AND token = '1u/pTO4IbLxl3zdp/cShQUboDkS0hF6pHBRM7tc73lE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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