SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '26a1c1d9ee8050d970e5314b0328e7e94aa87f66575ff71a4d360de8219ebb89' 
  AND token = '48O+ZSguKPg2BGyarCBMZAZkfA9jpwQf6uKYzmvoruc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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