SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e460a654e128726ea695e6110bf753c247172e13d3225b4f4555901456b8ad65' 
  AND token = '6BJWshekJfZFQDmxeI0IHuMuHvB1GVhBa2W6Xw4QcSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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