SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87fc96744406cd1e92652f15c0c1d41da29d6a7583ea594d39e134c5dc72ab00' 
  AND token = 'feSWIjNuxgBmElmGcya2E3OpSesXa6ptgc1QLUuHG6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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