Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6e5cc98e95f9837f251af5771b23b32e3c49918858ded07d716fd30661bb839' 
  AND token = 'B9v+xqyVOlf6bv6FELUVdl9n67nJ5S7j1HTdgV+kiFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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