---
title: Build the library
description: Build the example library database step by step — tables, a relationship, and some rows.
sidebar:
  order: 1
---

:::note[Draft]
This guide is an early draft. The walkthrough is correct, but the wording
and pacing will be refined for teaching before the docs are published.
:::

This guide builds the [example library](/getting-started/example-library/)
from scratch in simple mode: two tables, a relationship between them, and a
few rows. By the end you will have used the create → add column → relate →
insert → query loop end to end.

## 1. Create the authors table

```text
create table authors with pk author_id(serial)
add column to authors: name (text)
add column to authors: birth_year (int)
```

## 2. Create the books table

```text
create table books with pk book_id(serial)
add column to books: title (text)
add column to books: author_id (int)
add column to books: published (int)
```

## 3. Relate books to authors

An author has many books, so `books.author_id` should point at
`authors.author_id`. Declare that one-to-many relationship:

```text
add 1:n relationship from authors.author_id to books.author_id
```

The relationship reads parent-to-child: **from** the `authors` side **to**
the `books` side.

## 4. Add some rows

`author_id` and `book_id` are `serial`, so they fill themselves in:

```text
insert into authors (name, birth_year) values ('Ada Lovelace', 1815)
insert into authors (name, birth_year) values ('Alan Turing', 1912)
insert into books (title, author_id, published) values ('Notes on the Analytical Engine', 1, 1843)
```

## 5. Look at your data

```text
show data authors
show data books
```

## Where to go next

- Add the `members` and `loans` tables the same way to model borrowing — a
  many-to-many relationship through `loans`.
- Try the same steps in advanced mode to see the SQL form of each command.
- Look up any command in detail in the Reference section.