View Source AWS.SimpleDB (aws-elixir v0.13.3)
Amazon SimpleDB is a web service providing the core database functions of data indexing and querying in the cloud.
By offloading the time and effort associated with building and operating a web-scale database, SimpleDB provides developers the freedom to focus on application development. A traditional, clustered relational database requires a sizable upfront capital outlay, is complex to design, and often requires extensive and repetitive database administration. Amazon SimpleDB is dramatically simpler, requiring no schema, automatically indexing your data and providing a simple API for storage and access. This approach eliminates the administrative burden of data modeling, index maintenance, and performance tuning. Developers gain access to this functionality within Amazon's proven computing environment, are able to scale instantly, and pay only for what they use.
Visit http://aws.amazon.com/simpledb/ for more information.
Link to this section Summary
Functions
Performs multiple DeleteAttributes operations in a single call, which reduces round trips and latencies.
The BatchPutAttributes
operation creates or replaces attributes within one or
more items.
The CreateDomain
operation creates a new domain.
Deletes one or more attributes associated with an item.
The DeleteDomain
operation deletes a domain.
Returns information about the domain, including when the domain was created, the number of items and attributes in the domain, and the size of the attribute names and values.
Returns all of the attributes associated with the specified item.
The ListDomains
operation lists all domains associated with the Access Key ID.
The PutAttributes operation creates or replaces attributes in an item.
The Select
operation returns a set of attributes for ItemNames
that match
the select expression.
Link to this section Functions
Performs multiple DeleteAttributes operations in a single call, which reduces round trips and latencies.
This enables Amazon SimpleDB to optimize requests, which generally yields better throughput.
If you specify BatchDeleteAttributes without attributes or values, all the attributes for the item are deleted.
BatchDeleteAttributes is an idempotent operation; running it multiple times on the same item or attribute doesn't result in an error.
The BatchDeleteAttributes operation succeeds or fails in its entirety. There are no partial deletes. You can execute multiple BatchDeleteAttributes operations and other operations in parallel. However, large numbers of concurrent BatchDeleteAttributes calls can result in Service Unavailable (503) responses.
This operation is vulnerable to exceeding the maximum URL size when making a REST request using the HTTP GET method.
This operation does not support conditions using Expected.X.Name, Expected.X.Value, or Expected.X.Exists.
The following limitations are enforced for this operation:
- 1 MB request size
- 25 item limit per BatchDeleteAttributes operation
The BatchPutAttributes
operation creates or replaces attributes within one or
more items.
By using this operation, the client can perform multiple PutAttribute
operation with a single call. This helps yield savings in round trips and
latencies, enabling Amazon SimpleDB to optimize requests and generally produce
better throughput.
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" }
and { "first_name", "second_value" }
. However, it cannot have
two attribute instances where both the Item.X.Attribute.Y.Name
and
Item.X.Attribute.Y.Value
are the same.
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' }
and { 'b', '4' }
, replacing the previous values of the 'b' attribute with the new value.
You cannot specify an empty string as an item or as an attribute name. The
BatchPutAttributes
operation succeeds or fails in its entirety. There are no
partial puts.
This operation is vulnerable to exceeding the maximum URL size when making a
REST request using the HTTP GET method. This operation does not support
conditions using Expected.X.Name
, Expected.X.Value
, or Expected.X.Exists
.
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 CreateDomain
operation creates a new domain.
The domain name should be unique among the domains associated with the Access
Key ID provided in the request. The CreateDomain
operation may take 10 or more
seconds to complete.
CreateDomain is an idempotent operation; running it multiple times using the same domain name will not result in an error response.
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/.
Deletes one or more attributes associated with an item.
If all attributes of the item are deleted, the item is deleted.
If DeleteAttributes
is called without being passed any attributes or values
specified, all the attributes for the item are deleted.
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.
The DeleteDomain
operation deletes a domain.
Any items (and their attributes) in the domain are deleted as well. The
DeleteDomain
operation might take 10 or more seconds to complete.
Running DeleteDomain
on a domain that does not exist or running the function
multiple times using the same domain name will not result in an error response.
Returns information about the domain, including when the domain was created, the number of items and attributes in the domain, and the size of the attribute names and values.
Returns all of the attributes associated with the specified item.
Optionally, the attributes returned can be limited to one or more attributes by specifying an attribute name parameter.
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.
If GetAttributes is called without being passed any attribute names, all the attributes for the item are returned.
The ListDomains
operation lists all domains associated with the Access Key ID.
It returns domain names up to the limit set by
MaxNumberOfDomains. A NextToken is returned
if there are more than MaxNumberOfDomains
domains. Calling ListDomains
successive times with the NextToken
provided by the operation returns up to
MaxNumberOfDomains
more domain names with each successive operation call.
The PutAttributes operation creates or replaces attributes in an item.
The client may specify new attributes using a combination of the
Attribute.X.Name
and Attribute.X.Value
parameters. The client specifies the
first attribute by the parameters Attribute.0.Name
and Attribute.0.Value
,
the second attribute by the parameters Attribute.1.Name
and
Attribute.1.Value
, and so on.
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" }
and { "first_name", second_value" }
. However, it cannot have
two attribute instances where both the Attribute.X.Name
and
Attribute.X.Value
are the same.
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' }
and the requestor
calls PutAttributes
using the attributes { 'b', '4' }
with the Replace
parameter set to true, the final attributes of the item are changed to { 'a', '1' }
and { 'b', '4' }
, which replaces the previous values of the 'b'
attribute with the new value.
Using PutAttributes
to replace attribute values that do not exist will not
result in an error response.
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 Select
operation returns a set of attributes for ItemNames
that match
the select expression.
Select
is similar to the standard SQL SELECT statement.
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.