SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7559562ed414f9d54e8646970436fb7f29fd51a211cd2d355687b48cb958c28a' 
  AND token = 'Gnn7IUcTBoIJtAd9NC1YO87uDF5GBoBLnws/A9dNZUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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