SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c96744b9ddc4952e3b77e6f162f870145dcfdaf772bfe34951f20affd64b49e' 
  AND token = 'Gja4EgN5e96b3YdCrDMb0BhxRUmHDwulI89yIg72IWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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