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Foundations · Lesson 1 of 20

Items, not rows

Two items in one table can have completely different attributes.

Next · FoundationsThe key is the address

Why

A DynamoDB item is a bag of typed attributes, not a row in a fixed set of columns. The only attribute every item must have is the primary key.

Read the book, then the lamp. They live in the same table and share nothing but their id. Each attribute carries its type with it: S for a string, N for a number, BOOL for a boolean, SS for a string set.

Only the key is fixed. Every other attribute is decided item by item.

Inventory
Try an example

A book: it has a title, pages, and a set of tags.

id(pk)
kind
title
pages
tags
name
watts
inStock
lengthCm
when
soldOut
admin
species
waterDays
material
subject
priority
country
population
serves
vegetarian
body
done
percentOff
active

Run an operation to see the raw engine response.

table Inventorykeys iditems 15