Abstract: A forking coordinator of a journal-based multi-data-store database determines that a forking criterion for a first journal has been met. The coordinator stores an indication that processing of transaction requests directed to a particular subset of the database is suspended. The coordinator instantiates a second journal for storing committed transaction entries for the particular subset. Metadata of the second journal indicates that transaction entries with sequence numbers in a particular range are stored in the first journal. The coordinator stores an indication that transaction processing associated with the particular subset of the system is to be resumed using the second journal.

Abstract: A method and apparatus for the evaluation and remediation of an access control policy is disclosed. In the method and apparatus, an intermediary service may make access request, on behalf of a customer, to one or more computing resources and the access control policy is evaluation to determine whether the request is authorized. Further, remediation options for the access control policy are offered for the request to be authorized.

Abstract: A test coordinator for an application whose data is to be stored at a journal-based multi-data-store database using an optimistic concurrency control protocol identifies a test descriptor. The test descriptor indicates a particular order of a plurality of events associated with the application's data, such as reads from various data stores and propagations of committed writes from the database journal to the data stores. The test coordinator uses a set of control mechanisms to cause the events to occur in a selected execution environment in the particular order, and stores an indication of a state reached by the application in response to the events.

Abstract: A journaled database system may comprise data nodes that maintain a collection of data structured in accordance with a schema. A change to the schema may be applied by a journal module while a journal consumer continues to operate using a prior version of the schema. A buffer may be formed and have stored therein records describing state change instructions according to the prior view of the schema. An index of correspondence between the records in the buffer and in the source journal may be maintained.

Abstract: A journal manager of a multi-data-store storage appends a committed transaction entry to a journal, indicating a state change which has been approved for commit using an optimistic concurrency control algorithm. A first representation of the state change is generated and stored at one materialization node. A different representation of the same state change, comprising at least one attribute for which a value is not included in the first representation, is generated and stored at a different materialization node.

Abstract: A materialization configuration request is received via a programmatic interface from a client of a journal-based multi-data-store database. The request indicates a partitioning rule to be used to select, for respective writes indicated in committed transaction entries of a journal, the materialization node at which the writes are to be stored. A control plane component of the database verifies that a set of materialization nodes corresponding to the partitioning rule has been established, and initiates the propagation of writes from the journal to the materialization nodes by respective write appliers.

Abstract: A data store manager of a multi-data-store journal-based database performs a sequential analysis of committed transaction entries of a journal. A particular entry includes a directive to determine a value of an attribute of a data object based on a result obtained from a value generator, and does not specify the value of the attribute. The data store manager determines the value using a local version of the value generator, and stores the value in a materialized version of the data object. In response to a programmatic read request, the data store manager provides the materialized version of the data object.

Abstract: A materialization configuration request is received via a programmatic interface from a client of a journal-based multi-data-store database. The request indicates a partitioning rule to be used to select, for respective writes indicated in committed transaction entries of a journal, the materialization node at which the writes are to be stored. A control plane component of the database verifies that a set of materialization nodes corresponding to the partitioning rule has been established, and initiates the propagation of writes from the journal to the materialization nodes by respective write appliers.

Abstract: A system may comprise a storage device on which counters are stored. A counter may be associated with an identifier. A computing node of the system may receive a request to modify the counter. In response to the request, a read signature may be stored and may comprise a hash of the identifier and a tolerance of the counter to change. A write signature may be stored in response to the request, and may comprise a hash of the identifier and a magnitude of the requested modification. A conflict may be detected by comparing a sum of the magnitudes of requested changes to the tolerance of the read operation.

Abstract: A journal manager of a multi-data-store storage system receives a transaction which includes a message to be stored in the storage system's journal if the transaction request is accepted for commit. The journal manager performs a conflict detection operation, accepts the transaction request, and stores a corresponding committed transaction entry including the message in the journal. A write applier associated with a registered materialization node of the journal reads the committed transaction entry and applies a write indicated in the entry. A registered message subscriber of the journal reads the committed transaction entry asynchronously with respect to the write applier, and reads the contents of the message without applying the write.

Abstract: An authorization check web service request is disclosed. The web service request can include a parameter controlling whether or not to perform the action associated with the web service request. The parameter can be included in the web service request itself, or it can be separated therefrom, such as being included in a customer account. Using this parameter, the requestor can perform an authorization check without actually performing the action. Thus, customers can determine the authorization result of a request without actually processing the request itself. Customers and other services can use this parameter to determine their effective permissions.