IAmazonSimpleDB

The following limitations are enforced for this operation:

• 1 MB request size
• 25 item limit per BatchDeleteAttributes operation

The client may specify the item name with the Item.X.ItemName parameter. The client may specify new attributes using a combination of the Item.X.Attribute.Y.Name and Item.X.Attribute.Y.Value parameters. The client may specify the first attribute for the first item using the parameters Item.0.Attribute.0.Name and Item.0.Attribute.0.Value, and for the second attribute for the first item by the parameters Item.0.Attribute.1.Name and Item.0.Attribute.1.Value, and so on.

Attributes are uniquely identified within an item by their name/value combination. For example, a single item can have the attributes

{ "first_name", "first_value"
            }

Optionally, the requester can supply the Replace parameter for each individual value. Setting this value to true will cause the new attribute values to replace the existing attribute values. For example, if an item I has the attributes { 'a', '1' }, { 'b', '2'} and { 'b', '3' } and the requester does a BatchPutAttributes of {'I', 'b', '4' } with the Replace parameter set to true, the final attributes of the item will be

{
            'a', '1' }

You can execute multiple BatchPutAttributes operations and other operations in parallel. However, large numbers of concurrent BatchPutAttributes calls can result in Service Unavailable (503) responses.

The following limitations are enforced for this operation:

• 256 attribute name-value pairs per item
• 1 MB request size
• 1 billion attributes per domain
• 10 GB of total user data storage per domain
• 25 item limit per BatchPutAttributes operation

The client can create up to 100 domains per account.

If the client requires additional domains, go to http://aws.amazon.com/contact-us/simpledb-limit-request/.

DeleteAttributes is an idempotent operation; running it multiple times on the same item or attribute does not result in an error response.

Because Amazon SimpleDB makes multiple copies of item data and uses an eventual consistency update model, performing a GetAttributes or Select operation (read) immediately after a DeleteAttributes or PutAttributes operation (write) might not return updated item data.

If the item does not exist on the replica that was accessed for this operation, an empty set is returned. The system does not return an error as it cannot guarantee the item does not exist on other replicas.

Attributes are uniquely identified in an item by their name/value combination. For example, a single item can have the attributes

{ "first_name", "first_value"
            }

Optionally, the requestor can supply the Replace parameter for each individual attribute. Setting this value to true causes the new attribute value to replace the existing attribute value(s). For example, if an item has the attributes { 'a', '1' }, { 'b', '2'} and

{ 'b', '3'
            }

{
            'b', '4' }

You cannot specify an empty string as an attribute name.

Because Amazon SimpleDB makes multiple copies of client data and uses an eventual consistency update model, an immediate GetAttributes or Select operation (read) immediately after a PutAttributes or DeleteAttributes operation (write) might not return the updated data.

The following limitations are enforced for this operation:

• 256 total attribute name-value pairs per item
• One billion attributes per domain
• 10 GB of total user data storage per domain

The total size of the response cannot exceed 1 MB in total size. Amazon SimpleDB automatically adjusts the number of items returned per page to enforce this limit. For example, if the client asks to retrieve 2500 items, but each individual item is 10 kB in size, the system returns 100 items and an appropriate NextToken so the client can access the next page of results.

For information on how to construct select expressions, see Using Select to Create Amazon SimpleDB Queries in the Developer Guide.