Amazon DynamoDB Reader Parameters

AWS DynamoDB Connection

Specifies the region to use when connecting to Amazon Web Services, and dictates where tables are read from.

Note: Tables are region-dependent, so selecting an incorrect region will prevent your table from appearing in the table list.

When the Region is set to Other Region, this parameter is the entry point for the web service.

See AWS Endpoints for information about regional endpoints.

Specifies the Web Connection to use for authentication. If you're creating a new connection, selecting Embed Access Key auto populates the Access Key ID and Secret Access Key parameters with the provided credentials.

Web connections provide a convenient and secure way to store and reuse web connection parameters. For general information about web connections, please see Using Web Connections.

Allows the web connection credentials to be manually specified.

If Embed Access Key is selected, but credentials have not yet been provided, the reader will search for the credentials in various places, as defined below (see http://docs.aws.amazon.com).

Access Key ID

The AWS Access Key ID of the user who will access the database.

The user must exist in the database, and have appropriate permissions. If this entry is not found, the access key ID will be searched for in various places. These are, in order:

  • a file called AwsCredentials.properties on the Java classpath
  • aws.accessKeyId in the Java system properties
  • the environment variable AWS_ACCESS_KEY_ID

Once a pair of credentials is found, the search will stop.

Secret Access Key

The secret access key associated with the user accessing the database.

If this parameter is not found, the secret key will be searched for in various places. These are, in order:

  • a file called AwsCredentials.properties on the Java classpath
  • aws.secretKey in the Java system properties
  • the environment variable AWS_SECRET_KEY

The search will stop after a pair of credentials is found.

Constraints

Tables

After specifying the database connection, click the Browse button (...) to select tables for import. A connection window appears while the system retrieves the tables from the database.

Once the Select Tables dialog appears, you can select one or more tables. Click OK to dismiss the window and add the selected table name(s) to the Tables parameter.

Note: If the table list does not display your table, ensure that you have selected the appropriate region in the writer parameters. DynamoDB tables are region-dependent, so selecting an incorrect region will prevent your table from appearing in the table list.

If you wish to query against a table’s secondary index, you must select only that table from the Tables parameter.

After you have selected a table to import, click the Browse button (...) to select an optional secondary index to query against. A connection window appears while the system compiles a list of secondary indexes associated with the table named in the Tables parameter.

Once the index list appears, you can select one index, and then click OK to dismiss the window. The index name will appear in the Secondary Index field in the parameter box.

If a secondary index is selected, only a reader for the secondary index and not the table will be created.

Note: If you select a Secondary Index, the Specify Query Parameters below will use the keys from the Secondary Index.

If enabled, only items with a primary key that satisfy the specified key value conditions will be read from the table.

Partition Key Value

The partition key value of the items to read from the table.

Query Sort Key

If enabled, only items that satisfy both the partition key and sort key value conditions will be read from the table.

Sort Operator, Sort Key Value 1, Sort Key Value 2

Specifies the operator and values used to query sort keys. The following operators are supported:

= Only items with sort key values that match the value specified in Sort Key Value 1 are read.
< Only items with sort key values that are less than the value specified in Sort Key Value 1 are read.
<= Only items with sort key values that are less than or equal to the value specified in Sort Key Value 1 are read.
> Only items with sort key values that are greater than the value specified in Sort Key Value 1 are read.
>= Only items with sort key values that are greater than or equal to the value specified in Sort Key Value 1 are read.
Between Only items with sort key values that are greater than or equal to the value specified in Sort Key Value 1 and less than or equal to the value specified in Sort Key Value 2 are read.
Begins with Only items with sort key values that begin with the value specified in Sort Key Value 1 are read. This operator can only be used with sort keys of type string or binary.

Whether the reader outputs the original JSON for each item in the source table(s). If Yes, the original JSON is read into the dynamodb_json format attribute on each source feature.

If not set, dynamodb_json is not populated.

Additional Attributes to Expose

Use this parameter to expose Format Attributes in Workbench when you create a workspace:

  • In a dynamic scenario, it means these attributes can be passed to the output dataset at runtime.
  • In a non-dynamic scenario, this parameter allows you to expose additional attributes on multiple feature types. Click the browse button to view the available format attributes (which are different for each format) for the reader.