SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8520b563598fbe145fbd4a2c22ad43ebcc231b25ff6c70d13d917bb3c7bd0c56' 
  AND token = 'OeruypG454e+ulTD6Ptl/EqLuorsAHmgGXWf9oOV1ug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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