Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c50edf4ab3cecb1f1b6cb7b2d0b795b40e4e80b01d8c18d4b21a2d46f60d9f09' 
  AND token = 'Ph7XRwlATuiTAztUxf7WdrVoOr9P+uD4kekyqvy0gb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}