# Base Classes

All the base TypeScript classes in an ORM file that represent a table or view extend the base class [EntityBase](https://docs.wirebootstrap.com/orm/tables-and-views).  Similarly, all the base TypeScript classes that represent a stored procedure extend [ProcedureBase](https://docs.wirebootstrap.com/orm/stored-procedures).  

## Importing

These files can be imported from `wire-orm-base.ts`.

ORM structures can be imported individually from an ORM file.

```javascript
import { Categories } from "./northwind.orm.js";

const categories = await Categories.select().execAsync();
```

All structures in an ORM file can also be imported at one time using the `*` syntax.  In the example below, the `Northwind` variable acts as a namespace for all of the structures in the ORM file.  Any reference to a structure in the file will start with `Northwind`.

```typescript
import * as Northwind from "./northwind.orm.js";

const categories = await Northwind.Categories.select().execAsync();
```