public interface AmazonDynamoDB
This is the Amazon DynamoDB API Reference. This guide provides descriptions of the low-level DynamoDB API.
This guide is intended for use with the following DynamoDB documentation:
Amazon DynamoDB Getting Started Guide - provides hands-on exercises that help you learn the basics of working with DynamoDB. If you are new to DynamoDB, we recommend that you begin with the Getting Started Guide.
Amazon DynamoDB Developer Guide - contains detailed information about DynamoDB concepts, usage, and best practices.
Amazon DynamoDB Streams API Reference - provides descriptions and samples of the DynamoDB Streams API. (For more information, see Capturing Table Activity with DynamoDB Streams in the Amazon DynamoDB Developer Guide.)
Instead of making the requests to the low-level DynamoDB API directly from your application, we recommend that you use the AWS Software Development Kits (SDKs). The easy-to-use libraries in the AWS SDKs make it unnecessary to call the low-level DynamoDB API directly from your application. The libraries take care of request authentication, serialization, and connection management. For more information, see Using the AWS SDKs with DynamoDB in the Amazon DynamoDB Developer Guide.
If you decide to code against the low-level DynamoDB API directly, you will need to write the necessary code to authenticate your requests. For more information on signing your requests, see Using the DynamoDB API in the Amazon DynamoDB Developer Guide.
The following are short descriptions of each low-level API action, organized by function.
Managing Tables
CreateTable - Creates a table with user-specified provisioned throughput settings. You must define a primary key for the table - either a simple primary key (partition key), or a composite primary key (partition key and sort key). Optionally, you can create one or more secondary indexes, which provide fast data access using non-key attributes.
DescribeTable - Returns metadata for a table, such as table size, status, and index information.
UpdateTable - Modifies the provisioned throughput settings for a table. Optionally, you can modify the provisioned throughput settings for global secondary indexes on the table.
ListTables - Returns a list of all tables associated with the current AWS account and endpoint.
DeleteTable - Deletes a table and all of its indexes.
For conceptual information about managing tables, see Working with Tables in the Amazon DynamoDB Developer Guide.
Reading Data
GetItem - Returns a set of attributes for the item that has a given primary key. By default, GetItem performs an eventually consistent read; however, applications can request a strongly consistent read instead.
BatchGetItem - Performs multiple GetItem requests for data items using their primary keys, from one table or multiple tables. The response from BatchGetItem has a size limit of 16 MB and returns a maximum of 100 items. Both eventually consistent and strongly consistent reads can be used.
Query - Returns one or more items from a table or a secondary index. You must provide a specific value for the partition key. You can narrow the scope of the query using comparison operators against a sort key value, or on the index key. Query supports either eventual or strong consistency. A single response has a size limit of 1 MB.
Scan - Reads every item in a table; the result set is eventually consistent. You can limit the number of items returned by filtering the data attributes, using conditional expressions. Scan can be used to enable ad-hoc querying of a table against non-key attributes; however, since this is a full table scan without using an index, Scan should not be used for any application query use case that requires predictable performance.
For conceptual information about reading data, see Working with Items and Query and Scan Operations in the Amazon DynamoDB Developer Guide.
Modifying Data
PutItem - Creates a new item, or replaces an existing item with a new item (including all the attributes). By default, if an item in the table already exists with the same primary key, the new item completely replaces the existing item. You can use conditional operators to replace an item only if its attribute values match certain conditions, or to insert a new item only if that item doesn't already exist.
UpdateItem - Modifies the attributes of an existing item. You can also use conditional operators to perform an update only if the item's attribute values match certain conditions.
DeleteItem - Deletes an item in a table by primary key. You can use conditional operators to perform a delete an item only if the item's attribute values match certain conditions.
BatchWriteItem - Performs multiple PutItem and DeleteItem requests across multiple tables in a single request. A failure of any request(s) in the batch will not cause the entire BatchWriteItem operation to fail. Supports batches of up to 25 items to put or delete, with a maximum total request size of 16 MB.
For conceptual information about modifying data, see Working with Items and Query and Scan Operations in the Amazon DynamoDB Developer Guide.
Modifier and Type | Method and Description |
---|---|
BatchGetItemResult |
batchGetItem(BatchGetItemRequest batchGetItemRequest)
The BatchGetItem operation returns the attributes of one or more
items from one or more tables.
|
BatchGetItemResult |
batchGetItem(Map<String,KeysAndAttributes> requestItems)
Simplified method form for invoking the BatchGetItem operation.
|
BatchGetItemResult |
batchGetItem(Map<String,KeysAndAttributes> requestItems,
String returnConsumedCapacity)
Simplified method form for invoking the BatchGetItem operation.
|
BatchWriteItemResult |
batchWriteItem(BatchWriteItemRequest batchWriteItemRequest)
The BatchWriteItem operation puts or deletes multiple items in one
or more tables.
|
BatchWriteItemResult |
batchWriteItem(Map<String,List<WriteRequest>> requestItems)
Simplified method form for invoking the BatchWriteItem operation.
|
CreateTableResult |
createTable(CreateTableRequest createTableRequest)
The CreateTable operation adds a new table to your account.
|
CreateTableResult |
createTable(List<AttributeDefinition> attributeDefinitions,
String tableName,
List<KeySchemaElement> keySchema,
ProvisionedThroughput provisionedThroughput)
Simplified method form for invoking the CreateTable operation.
|
DeleteItemResult |
deleteItem(DeleteItemRequest deleteItemRequest)
Deletes a single item in a table by primary key.
|
DeleteItemResult |
deleteItem(String tableName,
Map<String,AttributeValue> key)
Simplified method form for invoking the DeleteItem operation.
|
DeleteItemResult |
deleteItem(String tableName,
Map<String,AttributeValue> key,
String returnValues)
Simplified method form for invoking the DeleteItem operation.
|
DeleteTableResult |
deleteTable(DeleteTableRequest deleteTableRequest)
The DeleteTable operation deletes a table and all of its items.
|
DeleteTableResult |
deleteTable(String tableName)
Simplified method form for invoking the DeleteTable operation.
|
DescribeLimitsResult |
describeLimits(DescribeLimitsRequest describeLimitsRequest)
Returns the current provisioned-capacity limits for your AWS account in a
region, both for the region as a whole and for any one DynamoDB table
that you create there.
|
DescribeTableResult |
describeTable(DescribeTableRequest describeTableRequest)
Returns information about the table, including the current status of the
table, when it was created, the primary key schema, and any indexes on
the table.
|
DescribeTableResult |
describeTable(String tableName)
Simplified method form for invoking the DescribeTable operation.
|
ResponseMetadata |
getCachedResponseMetadata(AmazonWebServiceRequest request)
Returns additional metadata for a previously executed successful request,
typically used for debugging issues where a service isn't acting as
expected.
|
GetItemResult |
getItem(GetItemRequest getItemRequest)
The GetItem operation returns a set of attributes for the item
with the given primary key.
|
GetItemResult |
getItem(String tableName,
Map<String,AttributeValue> key)
Simplified method form for invoking the GetItem operation.
|
GetItemResult |
getItem(String tableName,
Map<String,AttributeValue> key,
Boolean consistentRead)
Simplified method form for invoking the GetItem operation.
|
ListTablesResult |
listTables()
Simplified method form for invoking the ListTables operation.
|
ListTablesResult |
listTables(Integer limit)
Simplified method form for invoking the ListTables operation.
|
ListTablesResult |
listTables(ListTablesRequest listTablesRequest)
Returns an array of table names associated with the current account and
endpoint.
|
ListTablesResult |
listTables(String exclusiveStartTableName)
Simplified method form for invoking the ListTables operation.
|
ListTablesResult |
listTables(String exclusiveStartTableName,
Integer limit)
Simplified method form for invoking the ListTables operation.
|
PutItemResult |
putItem(PutItemRequest putItemRequest)
Creates a new item, or replaces an old item with a new item.
|
PutItemResult |
putItem(String tableName,
Map<String,AttributeValue> item)
Simplified method form for invoking the PutItem operation.
|
PutItemResult |
putItem(String tableName,
Map<String,AttributeValue> item,
String returnValues)
Simplified method form for invoking the PutItem operation.
|
QueryResult |
query(QueryRequest queryRequest)
A Query operation uses the primary key of a table or a secondary
index to directly access items from that table or index.
|
ScanResult |
scan(ScanRequest scanRequest)
The Scan operation returns one or more items and item attributes
by accessing every item in a table or a secondary index.
|
ScanResult |
scan(String tableName,
List<String> attributesToGet)
Simplified method form for invoking the Scan operation.
|
ScanResult |
scan(String tableName,
List<String> attributesToGet,
Map<String,Condition> scanFilter)
Simplified method form for invoking the Scan operation.
|
ScanResult |
scan(String tableName,
Map<String,Condition> scanFilter)
Simplified method form for invoking the Scan operation.
|
void |
setEndpoint(String endpoint)
Overrides the default endpoint for this client
("https://dynamodb.us-east-1.amazonaws.com").
|
void |
setRegion(Region region)
An alternative to
setEndpoint(String) , sets the
regional endpoint for this client's service calls. |
void |
shutdown()
Shuts down this client object, releasing any resources that might be held
open.
|
UpdateItemResult |
updateItem(String tableName,
Map<String,AttributeValue> key,
Map<String,AttributeValueUpdate> attributeUpdates)
Simplified method form for invoking the UpdateItem operation.
|
UpdateItemResult |
updateItem(String tableName,
Map<String,AttributeValue> key,
Map<String,AttributeValueUpdate> attributeUpdates,
String returnValues)
Simplified method form for invoking the UpdateItem operation.
|
UpdateItemResult |
updateItem(UpdateItemRequest updateItemRequest)
Edits an existing item's attributes, or adds a new item to the table if
it does not already exist.
|
UpdateTableResult |
updateTable(String tableName,
ProvisionedThroughput provisionedThroughput)
Simplified method form for invoking the UpdateTable operation.
|
UpdateTableResult |
updateTable(UpdateTableRequest updateTableRequest)
Modifies the provisioned throughput settings, global secondary indexes,
or DynamoDB Streams settings for a given table.
|
void setEndpoint(String endpoint)
Callers can pass in just the endpoint (ex:
"dynamodb.us-east-1.amazonaws.com") or a full URL, including the protocol
(ex: "https://dynamodb.us-east-1.amazonaws.com"). If the protocol is not
specified here, the default protocol from this client's
ClientConfiguration
will be used, which by default is HTTPS.
For more information on using AWS regions with the AWS SDK for Java, and a complete list of all available endpoints for all AWS services, see: http://developer.amazonwebservices.com/connect/entry.jspa?externalID= 3912
This method is not threadsafe. An endpoint should be configured when the client is created and before any service requests are made. Changing it afterwards creates inevitable race conditions for any service requests in transit or retrying.
endpoint
- The endpoint (ex: "dynamodb.us-east-1.amazonaws.com") or a full
URL, including the protocol (ex:
"https://dynamodb.us-east-1.amazonaws.com") of the region specific
AWS endpoint this client will communicate with.void setRegion(Region region)
setEndpoint(String)
, sets the
regional endpoint for this client's service calls. Callers can use this
method to control which AWS region they want to work with.
By default, all service endpoints in all regions use the https protocol.
To use http instead, specify it in the ClientConfiguration
supplied at construction.
This method is not threadsafe. A region should be configured when the client is created and before any service requests are made. Changing it afterwards creates inevitable race conditions for any service requests in transit or retrying.
region
- The region this client will communicate with. See
Region.getRegion(com.amazonaws.regions.Regions)
for
accessing a given region. Must not be null and must be a region
where the service is available.Region.getRegion(com.amazonaws.regions.Regions)
,
Region.createClient(Class,
com.amazonaws.auth.AWSCredentialsProvider, ClientConfiguration)
,
Region.isServiceSupported(String)
BatchGetItemResult batchGetItem(BatchGetItemRequest batchGetItemRequest)
The BatchGetItem operation returns the attributes of one or more items from one or more tables. You identify requested items by primary key.
A single operation can retrieve up to 16 MB of data, which can contain as many as 100 items. BatchGetItem will return a partial result if the response size limit is exceeded, the table's provisioned throughput is exceeded, or an internal processing failure occurs. If a partial result is returned, the operation returns a value for UnprocessedKeys. You can use this value to retry the operation starting with the next item to get.
If you request more than 100 items BatchGetItem will return a ValidationException with the message "Too many items requested for the BatchGetItem call".
For example, if you ask to retrieve 100 items, but each individual item is 300 KB in size, the system returns 52 items (so as not to exceed the 16 MB limit). It also returns an appropriate UnprocessedKeys value so you can get the next page of results. If desired, your application can include its own logic to assemble the pages of results into one data set.
If none of the items can be processed due to insufficient provisioned throughput on all of the tables in the request, then BatchGetItem will return a ProvisionedThroughputExceededException. If at least one of the items is successfully processed, then BatchGetItem completes successfully, while returning the keys of the unread items in UnprocessedKeys.
If DynamoDB returns any unprocessed items, you should retry the batch operation on those items. However, we strongly recommend that you use an exponential backoff algorithm. If you retry the batch operation immediately, the underlying read or write requests can still fail due to throttling on the individual tables. If you delay the batch operation using exponential backoff, the individual requests in the batch are much more likely to succeed.
For more information, see Batch Operations and Error Handling in the Amazon DynamoDB Developer Guide.
By default, BatchGetItem performs eventually consistent reads on
every table in the request. If you want strongly consistent reads
instead, you can set ConsistentRead to true
for any
or all tables.
In order to minimize response latency, BatchGetItem retrieves items in parallel.
When designing your application, keep in mind that DynamoDB does not return attributes in any particular order. To help parse the response by item, include the primary key values for the items in your request in the AttributesToGet parameter.
If a requested item does not exist, it is not returned in the result. Requests for nonexistent items consume the minimum read capacity units according to the type of read. For more information, see Capacity Units Calculations in the Amazon DynamoDB Developer Guide.
batchGetItemRequest
- Represents the input of a BatchGetItem operation.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.InternalServerErrorException
- An error occurred on the server side.BatchGetItemResult batchGetItem(Map<String,KeysAndAttributes> requestItems, String returnConsumedCapacity)
batchGetItem(BatchGetItemRequest)
BatchGetItemResult batchGetItem(Map<String,KeysAndAttributes> requestItems)
batchGetItem(BatchGetItemRequest)
BatchWriteItemResult batchWriteItem(BatchWriteItemRequest batchWriteItemRequest)
The BatchWriteItem operation puts or deletes multiple items in one or more tables. A single call to BatchWriteItem can write up to 16 MB of data, which can comprise as many as 25 put or delete requests. Individual items to be written can be as large as 400 KB.
BatchWriteItem cannot update items. To update items, use the UpdateItem API.
The individual PutItem and DeleteItem operations specified in BatchWriteItem are atomic; however BatchWriteItem as a whole is not. If any requested operations fail because the table's provisioned throughput is exceeded or an internal processing failure occurs, the failed operations are returned in the UnprocessedItems response parameter. You can investigate and optionally resend the requests. Typically, you would call BatchWriteItem in a loop. Each iteration would check for unprocessed items and submit a new BatchWriteItem request with those unprocessed items until all items have been processed.
Note that if none of the items can be processed due to insufficient provisioned throughput on all of the tables in the request, then BatchWriteItem will return a ProvisionedThroughputExceededException.
If DynamoDB returns any unprocessed items, you should retry the batch operation on those items. However, we strongly recommend that you use an exponential backoff algorithm. If you retry the batch operation immediately, the underlying read or write requests can still fail due to throttling on the individual tables. If you delay the batch operation using exponential backoff, the individual requests in the batch are much more likely to succeed.
For more information, see Batch Operations and Error Handling in the Amazon DynamoDB Developer Guide.
With BatchWriteItem, you can efficiently write or delete large amounts of data, such as from Amazon Elastic MapReduce (EMR), or copy data from another database into DynamoDB. In order to improve performance with these large-scale operations, BatchWriteItem does not behave in the same way as individual PutItem and DeleteItem calls would. For example, you cannot specify conditions on individual put and delete requests, and BatchWriteItem does not return deleted items in the response.
If you use a programming language that supports concurrency, you can use threads to write items in parallel. Your application must include the necessary logic to manage the threads. With languages that don't support threading, you must update or delete the specified items one at a time. In both situations, BatchWriteItem provides an alternative where the API performs the specified put and delete operations in parallel, giving you the power of the thread pool approach without having to introduce complexity into your application.
Parallel processing reduces latency, but each specified put and delete request consumes the same number of write capacity units whether it is processed in parallel or not. Delete operations on nonexistent items consume one write capacity unit.
If one or more of the following is true, DynamoDB rejects the entire batch write operation:
One or more tables specified in the BatchWriteItem request does not exist.
Primary key attributes specified on an item in the request do not match those in the corresponding table's primary key schema.
You try to perform multiple operations on the same item in the same BatchWriteItem request. For example, you cannot put and delete the same item in the same BatchWriteItem request.
There are more than 25 requests in the batch.
Any individual item in a batch exceeds 400 KB.
The total request size exceeds 16 MB.
batchWriteItemRequest
- Represents the input of a BatchWriteItem operation.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.ItemCollectionSizeLimitExceededException
- An item collection is too large. This exception is only returned
for tables that have one or more local secondary indexes.InternalServerErrorException
- An error occurred on the server side.BatchWriteItemResult batchWriteItem(Map<String,List<WriteRequest>> requestItems)
CreateTableResult createTable(CreateTableRequest createTableRequest)
The CreateTable operation adds a new table to your account. In an AWS account, table names must be unique within each region. That is, you can have two tables with same name if you create the tables in different regions.
CreateTable is an asynchronous operation. Upon receiving a
CreateTable request, DynamoDB immediately returns a response with
a TableStatus of CREATING
. After the table is
created, DynamoDB sets the TableStatus to ACTIVE
. You
can perform read and write operations only on an ACTIVE
table.
You can optionally define secondary indexes on the new table, as part of
the CreateTable operation. If you want to create multiple tables
with secondary indexes on them, you must create the tables sequentially.
Only one table with secondary indexes can be in the CREATING
state at any given time.
You can use the DescribeTable API to check the table status.
createTableRequest
- Represents the input of a CreateTable operation.ResourceInUseException
- The operation conflicts with the resource's availability. For
example, you attempted to recreate an existing table, or tried to
delete a table currently in the CREATING
state.LimitExceededException
- The number of concurrent table requests (cumulative number of
tables in the CREATING
, DELETING
or
UPDATING
state) exceeds the maximum allowed of
10.
Also, for tables with secondary indexes, only one of those tables
can be in the CREATING
state at any point in time.
Do not attempt to create more than one such table simultaneously.
The total limit of tables in the ACTIVE
state is
250.
InternalServerErrorException
- An error occurred on the server side.CreateTableResult createTable(List<AttributeDefinition> attributeDefinitions, String tableName, List<KeySchemaElement> keySchema, ProvisionedThroughput provisionedThroughput)
createTable(CreateTableRequest)
DeleteItemResult deleteItem(DeleteItemRequest deleteItemRequest)
Deletes a single item in a table by primary key. You can perform a conditional delete operation that deletes the item if it exists, or if it has an expected attribute value.
In addition to deleting an item, you can also return the item's attribute values in the same operation, using the ReturnValues parameter.
Unless you specify conditions, the DeleteItem is an idempotent operation; running it multiple times on the same item or attribute does not result in an error response.
Conditional deletes are useful for deleting items only if specific conditions are met. If those conditions are met, DynamoDB performs the delete. Otherwise, the item is not deleted.
deleteItemRequest
- Represents the input of a DeleteItem operation.ConditionalCheckFailedException
- A condition specified in the operation could not be evaluated.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.ItemCollectionSizeLimitExceededException
- An item collection is too large. This exception is only returned
for tables that have one or more local secondary indexes.InternalServerErrorException
- An error occurred on the server side.DeleteItemResult deleteItem(String tableName, Map<String,AttributeValue> key)
deleteItem(DeleteItemRequest)
DeleteItemResult deleteItem(String tableName, Map<String,AttributeValue> key, String returnValues)
deleteItem(DeleteItemRequest)
DeleteTableResult deleteTable(DeleteTableRequest deleteTableRequest)
The DeleteTable operation deletes a table and all of its items.
After a DeleteTable request, the specified table is in the
DELETING
state until DynamoDB completes the deletion. If the
table is in the ACTIVE
state, you can delete it. If a table
is in CREATING
or UPDATING
states, then
DynamoDB returns a ResourceInUseException. If the specified table
does not exist, DynamoDB returns a ResourceNotFoundException. If
table is already in the DELETING
state, no error is
returned.
DynamoDB might continue to accept data read and write operations, such as
GetItem and PutItem, on a table in the
DELETING
state until the table deletion is complete.
When you delete a table, any indexes on that table are also deleted.
If you have DynamoDB Streams enabled on the table, then the corresponding
stream on that table goes into the DISABLED
state, and the
stream is automatically deleted after 24 hours.
Use the DescribeTable API to check the status of the table.
deleteTableRequest
- Represents the input of a DeleteTable operation.ResourceInUseException
- The operation conflicts with the resource's availability. For
example, you attempted to recreate an existing table, or tried to
delete a table currently in the CREATING
state.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.LimitExceededException
- The number of concurrent table requests (cumulative number of
tables in the CREATING
, DELETING
or
UPDATING
state) exceeds the maximum allowed of
10.
Also, for tables with secondary indexes, only one of those tables
can be in the CREATING
state at any point in time.
Do not attempt to create more than one such table simultaneously.
The total limit of tables in the ACTIVE
state is
250.
InternalServerErrorException
- An error occurred on the server side.DeleteTableResult deleteTable(String tableName)
deleteTable(DeleteTableRequest)
DescribeLimitsResult describeLimits(DescribeLimitsRequest describeLimitsRequest)
Returns the current provisioned-capacity limits for your AWS account in a region, both for the region as a whole and for any one DynamoDB table that you create there.
When you establish an AWS account, the account has initial limits on the maximum read capacity units and write capacity units that you can provision across all of your DynamoDB tables in a given region. Also, there are per-table limits that apply when you create a table there. For more information, see Limits page in the Amazon DynamoDB Developer Guide.
Although you can increase these limits by filing a case at AWS Support Center, obtaining the increase is not instantaneous. The DescribeLimits API lets you write code to compare the capacity you are currently using to those limits imposed by your account so that you have enough time to apply for an increase before you hit a limit.
For example, you could use one of the AWS SDKs to do the following:
For each table name listed by ListTables, do the following:
This will let you see whether you are getting close to your account-level limits.
The per-table limits apply only when you are creating a new table. They restrict the sum of the provisioned capacity of the new table itself and all its global secondary indexes.
For existing tables and their GSIs, DynamoDB will not let you increase provisioned capacity extremely rapidly, but the only upper limit that applies is that the aggregate provisioned capacity over all your tables and GSIs cannot exceed either of the per-account limits.
DescribeLimits should only be called periodically. You can expect throttling errors if you call it more than once in a minute.
The DescribeLimits Request element has no content.
describeLimitsRequest
- Represents the input of a DescribeLimits operation. Has no
content.InternalServerErrorException
- An error occurred on the server side.DescribeTableResult describeTable(DescribeTableRequest describeTableRequest)
Returns information about the table, including the current status of the table, when it was created, the primary key schema, and any indexes on the table.
If you issue a DescribeTable request immediately after a CreateTable request, DynamoDB might return a ResourceNotFoundException. This is because DescribeTable uses an eventually consistent query, and the metadata for your table might not be available at that moment. Wait for a few seconds, and then try the DescribeTable request again.
describeTableRequest
- Represents the input of a DescribeTable operation.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.InternalServerErrorException
- An error occurred on the server side.DescribeTableResult describeTable(String tableName)
describeTable(DescribeTableRequest)
GetItemResult getItem(GetItemRequest getItemRequest)
The GetItem operation returns a set of attributes for the item with the given primary key. If there is no matching item, GetItem does not return any data.
GetItem provides an eventually consistent read by default. If your
application requires a strongly consistent read, set
ConsistentRead to true
. Although a strongly
consistent read might take more time than an eventually consistent read,
it always returns the last updated value.
getItemRequest
- Represents the input of a GetItem operation.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.InternalServerErrorException
- An error occurred on the server side.GetItemResult getItem(String tableName, Map<String,AttributeValue> key)
getItem(GetItemRequest)
GetItemResult getItem(String tableName, Map<String,AttributeValue> key, Boolean consistentRead)
getItem(GetItemRequest)
ListTablesResult listTables(ListTablesRequest listTablesRequest)
Returns an array of table names associated with the current account and endpoint. The output from ListTables is paginated, with each page returning a maximum of 100 table names.
listTablesRequest
- Represents the input of a ListTables operation.InternalServerErrorException
- An error occurred on the server side.ListTablesResult listTables()
listTables(ListTablesRequest)
ListTablesResult listTables(String exclusiveStartTableName)
listTables(ListTablesRequest)
ListTablesResult listTables(String exclusiveStartTableName, Integer limit)
listTables(ListTablesRequest)
ListTablesResult listTables(Integer limit)
listTables(ListTablesRequest)
PutItemResult putItem(PutItemRequest putItemRequest)
Creates a new item, or replaces an old item with a new item. If an item that has the same primary key as the new item already exists in the specified table, the new item completely replaces the existing item. You can perform a conditional put operation (add a new item if one with the specified primary key doesn't exist), or replace an existing item if it has certain attribute values.
In addition to putting an item, you can also return the item's attribute values in the same operation, using the ReturnValues parameter.
When you add an item, the primary key attribute(s) are the only required attributes. Attribute values cannot be null. String and Binary type attributes must have lengths greater than zero. Set type attributes cannot be empty. Requests with empty values will be rejected with a ValidationException exception.
You can request that PutItem return either a copy of the original item (before the update) or a copy of the updated item (after the update). For more information, see the ReturnValues description below.
To prevent a new item from replacing an existing item, use a conditional
expression that contains the attribute_not_exists
function
with the name of the attribute being used as the partition key for the
table. Since every record must contain that attribute, the
attribute_not_exists
function will only succeed if no
matching item exists.
For more information about using this API, see Working with Items in the Amazon DynamoDB Developer Guide.
putItemRequest
- Represents the input of a PutItem operation.ConditionalCheckFailedException
- A condition specified in the operation could not be evaluated.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.ItemCollectionSizeLimitExceededException
- An item collection is too large. This exception is only returned
for tables that have one or more local secondary indexes.InternalServerErrorException
- An error occurred on the server side.PutItemResult putItem(String tableName, Map<String,AttributeValue> item)
putItem(PutItemRequest)
PutItemResult putItem(String tableName, Map<String,AttributeValue> item, String returnValues)
putItem(PutItemRequest)
QueryResult query(QueryRequest queryRequest)
A Query operation uses the primary key of a table or a secondary index to directly access items from that table or index.
Use the KeyConditionExpression parameter to provide a specific value for the partition key. The Query operation will return all of the items from the table or index with that partition key value. You can optionally narrow the scope of the Query operation by specifying a sort key value and a comparison operator in KeyConditionExpression. You can use the ScanIndexForward parameter to get results in forward or reverse order, by sort key.
Queries that do not return results consume the minimum number of read capacity units for that type of read operation.
If the total number of items meeting the query criteria exceeds the result set size limit of 1 MB, the query stops and results are returned to the user with the LastEvaluatedKey element to continue the query in a subsequent operation. Unlike a Scan operation, a Query operation never returns both an empty result set and a LastEvaluatedKey value. LastEvaluatedKey is only provided if the results exceed 1 MB, or if you have used the Limit parameter.
You can query a table, a local secondary index, or a global secondary
index. For a query on a table or on a local secondary index, you can set
the ConsistentRead parameter to true
and obtain a
strongly consistent result. Global secondary indexes support eventually
consistent reads only, so do not specify ConsistentRead when
querying a global secondary index.
queryRequest
- Represents the input of a Query operation.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.InternalServerErrorException
- An error occurred on the server side.ScanResult scan(ScanRequest scanRequest)
The Scan operation returns one or more items and item attributes by accessing every item in a table or a secondary index. To have DynamoDB return fewer items, you can provide a ScanFilter operation.
If the total number of scanned items exceeds the maximum data set size limit of 1 MB, the scan stops and results are returned to the user as a LastEvaluatedKey value to continue the scan in a subsequent operation. The results also include the number of items exceeding the limit. A scan can result in no table data meeting the filter criteria.
By default, Scan operations proceed sequentially; however, for faster performance on a large table or secondary index, applications can request a parallel Scan operation by providing the Segment and TotalSegments parameters. For more information, see Parallel Scan in the Amazon DynamoDB Developer Guide.
By default, Scan uses eventually consistent reads when accessing the data in a table; therefore, the result set might not include the changes to data in the table immediately before the operation began. If you need a consistent copy of the data, as of the time that the Scan begins, you can set the ConsistentRead parameter to true.
scanRequest
- Represents the input of a Scan operation.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.InternalServerErrorException
- An error occurred on the server side.ScanResult scan(String tableName, List<String> attributesToGet)
scan(ScanRequest)
ScanResult scan(String tableName, Map<String,Condition> scanFilter)
scan(ScanRequest)
ScanResult scan(String tableName, List<String> attributesToGet, Map<String,Condition> scanFilter)
scan(ScanRequest)
UpdateItemResult updateItem(UpdateItemRequest updateItemRequest)
Edits an existing item's attributes, or adds a new item to the table if it does not already exist. You can put, delete, or add attribute values. You can also perform a conditional update on an existing item (insert a new attribute name-value pair if it doesn't exist, or replace an existing name-value pair if it has certain expected attribute values).
You can also return the item's attribute values in the same UpdateItem operation using the ReturnValues parameter.
updateItemRequest
- Represents the input of an UpdateItem operation.ConditionalCheckFailedException
- A condition specified in the operation could not be evaluated.ProvisionedThroughputExceededException
- Your request rate is too high. The AWS SDKs for DynamoDB
automatically retry requests that receive this exception. Your
request is eventually successful, unless your retry queue is too
large to finish. Reduce the frequency of requests and use
exponential backoff. For more information, go to Error Retries and Exponential Backoff in the Amazon
DynamoDB Developer Guide.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.ItemCollectionSizeLimitExceededException
- An item collection is too large. This exception is only returned
for tables that have one or more local secondary indexes.InternalServerErrorException
- An error occurred on the server side.UpdateItemResult updateItem(String tableName, Map<String,AttributeValue> key, Map<String,AttributeValueUpdate> attributeUpdates)
updateItem(UpdateItemRequest)
UpdateItemResult updateItem(String tableName, Map<String,AttributeValue> key, Map<String,AttributeValueUpdate> attributeUpdates, String returnValues)
updateItem(UpdateItemRequest)
UpdateTableResult updateTable(UpdateTableRequest updateTableRequest)
Modifies the provisioned throughput settings, global secondary indexes, or DynamoDB Streams settings for a given table.
You can only perform one of the following operations at once:
Modify the provisioned throughput settings of the table.
Enable or disable Streams on the table.
Remove a global secondary index from the table.
Create a new global secondary index on the table. Once the index begins backfilling, you can use UpdateTable to perform other operations.
UpdateTable is an asynchronous operation; while it is executing,
the table status changes from ACTIVE
to
UPDATING
. While it is UPDATING
, you cannot
issue another UpdateTable request. When the table returns to the
ACTIVE
state, the UpdateTable operation is complete.
updateTableRequest
- Represents the input of an UpdateTable operation.ResourceInUseException
- The operation conflicts with the resource's availability. For
example, you attempted to recreate an existing table, or tried to
delete a table currently in the CREATING
state.ResourceNotFoundException
- The operation tried to access a nonexistent table or index. The
resource might not be specified correctly, or its status might
not be ACTIVE
.LimitExceededException
- The number of concurrent table requests (cumulative number of
tables in the CREATING
, DELETING
or
UPDATING
state) exceeds the maximum allowed of
10.
Also, for tables with secondary indexes, only one of those tables
can be in the CREATING
state at any point in time.
Do not attempt to create more than one such table simultaneously.
The total limit of tables in the ACTIVE
state is
250.
InternalServerErrorException
- An error occurred on the server side.UpdateTableResult updateTable(String tableName, ProvisionedThroughput provisionedThroughput)
updateTable(UpdateTableRequest)
void shutdown()
ResponseMetadata getCachedResponseMetadata(AmazonWebServiceRequest request)
Response metadata is only cached for a limited period of time, so if you need to access this extra diagnostic information for an executed request, you should use this method to retrieve it as soon as possible after executing a request.
request
- The originally executed request.Copyright © 2016. All rights reserved.