SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe2315930afb0d794069cfab94838314ee338811240265d39c031bc96331934d' 
  AND token = 'XJroicJpeS/6XLiIjFYBDUEuBaP66NKqDfJS2RtTDwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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