# The Great Age Conversion Crisis

DB Quacks SQL Tutorial · level 7 · chapter 2

An elegant swan with a golden medal glides over. "Emergency! The Duck Olympics start tomorrow but some countries measure age in years, others in months! We need every duck's age converted to months for fair competition."

## Task

Show duck names and their ages converted to months (multiply age by 12) from the ducks table. You will be performing mathematical calculations in your SELECT statement.

## Hint

You can perform calculations directly in your SELECT clause - think about how to multiply the age column by 12.

## Expected result

A table of duck names and their calculated age in months.

## Tables

### `duck_diaries` (10 rows)

| column | type |
| --- | --- |
| diary_id | BIGINT |
| duck_id | BIGINT |
| entry_date | DATE |
| diary_text | VARCHAR |
| mood | VARCHAR |

### `duck_surveys` (5000 rows)

| column | type |
| --- | --- |
| survey_id | BIGINT |
| duck_id | BIGINT |
| age | BIGINT |
| favorite_food | VARCHAR |
| favorite_pond | BIGINT |
| swimming_rating | BIGINT |
| migration_preference | VARCHAR |
| social_behavior | VARCHAR |
| health_status | VARCHAR |
| activity_level | VARCHAR |
| survey_date | DATE |
| survey_location | BIGINT |

### `ducks` (15 rows)

| column | type |
| --- | --- |
| id | BIGINT |
| name | VARCHAR |
| age | BIGINT |
| species | VARCHAR |
| birth_date | DATE |
| arrival_date | DATE |

### `ponds` (3 rows)

| column | type |
| --- | --- |
| pond_id | BIGINT |
| pond_name | VARCHAR |
| location_lat | DOUBLE |
| location_lng | DOUBLE |
| capacity | BIGINT |
| features | VARCHAR[] |
| amenities | VARCHAR[] |

## Data

The tables live in a DuckDB database: https://dbquacks.com/data/databases/tutorial.duckdb

To query it outside the browser, attach it read-only:

```sql
ATTACH 'https://dbquacks.com/data/databases/tutorial.duckdb' AS db (READ_ONLY);
USE db;
```

Play it in the browser: https://dbquacks.com/tutorial/7

## Reference

https://duckdb.org/docs/stable/sql/statements/select.html