CRUD Operations

Create / Save

product = Product(
    product_id="prod-123",
    name="Widget",
    price=29.99,
    in_stock=True
)
product.save()

Create with Condition (Insert-if-not-exists)

product.save(condition=Product.product_id.not_exists())

This raises ConditionalCheckFailedError if the item already exists.

INSERT Semantics with create()

For models with Auto-UUID keys, create() guarantees insert-only semantics:

class Task(DynamoModel):
    task_id: str = Key(auto=True)
    title: str

    class Meta:
        table_name = "tasks"

task = Task(title="Buy groceries")
task.create()  # Generates UUID and saves with condition check

Read / Get

# By partition key only
product = Product.get("prod-123")

# By partition + sort key
order = Order.get("customer-456", "order-789")

# Returns None if not found (no exception)
missing = Product.get("nonexistent")  # None

Info

get() always returns None for missing items — never raises an exception.

Update

Fetch-then-save

product = Product.get("prod-123")
product.price = 34.99
product.save()

Atomic updates (no fetch required)

For atomic, server-side updates without a round-trip, see Atomic Updates.

Product.update("prod-123") \
    .set(Product.price, 34.99) \
    .execute()

Delete

# By key (no fetch required)
Product.delete("prod-123")

# From instance
product = Product.get("prod-123")
product.delete_item()

# With condition
Product.delete("prod-123", condition=Product.in_stock == False)