Abstract: A transfer segment group task processing module of a database system is operable to send a first begin segment group transfer instruction to a first storage cluster based on a determination to transfer a set of segments stored via the first storage cluster to a second storage cluster. A target first ownership sequence number is received from the first storage cluster. A second begin segment group transfer instruction to the second storage cluster. A transfer complete notification is received from the second storage cluster. A complete storage instruction is sent to the second storage cluster. An updated second ownership sequence number is received from the second storage cluster indicating updating of second data ownership information of the second storage cluster. A commit transfer instruction is sent to the first storage cluster based on updated second ownership sequence number received from the second storage cluster.

Abstract: A database system is operable to assign a first node as a task monitoring node for a task and assign a second node as a task execution node for the task. The task is executed via the first node and the second node based on the first node sending a plurality of polls to the second node, the second node initiating execution of the task based on one of the plurality of polls, the second node sending a plurality of task status data to the first node, the first node maintaining current task status data for the task a shared metadata state based on the plurality of task status data, the second node completing execution of the task and caching task results in memory resources, the first node receiving the task results from the second node; and the second node removing the task results from the memory resources.

Abstract: A database system operates by: generating first segment addendum data indicating at least one addendum part indicating at least one change to a first segment of a plurality of segments, updating segment part activation data to indicate a first ownership sequence number (OSN) range for activation of the first segment addendum data during query execution, executing a first query, having a first ownership sequence number, based on accessing the first segment in response to first data ownership information tagged with the first ownership sequence number indicating activation of the first segment, and further based on foregoing applying of the at least one addendum part for the first segment in response to the first ownership sequence number falling outside of the first OSN range indicated in the segment part activation data for the first segment addendum data, and executing a second query, having a second ownership sequence number, based on accessing the first segment in response to second data ownership informat

Abstract: A transfer segment group task processing module of a database system is operable to send a first begin segment group transfer instruction to a first storage cluster based on a determination to transfer a set of segments stored via the first storage cluster to a second storage cluster. A target first ownership sequence number is received from the first storage cluster. A second begin segment group transfer instruction to the second storage cluster. A transfer complete notification is received from the second storage cluster. A complete storage instruction is sent to the second storage cluster. An updated second ownership sequence number is received from the second storage cluster indicating updating of second data ownership information of the second storage cluster. A commit transfer instruction is sent to the first storage cluster based on updated second ownership sequence number received from the second storage cluster.

Abstract: A node of a database system is operable to determine, at a first time, to prepare for a shutdown. The shutdown of the node is performed at a second time that is a period of time after the first time based on the node delaying the shutdown until a plurality of currently running processes being run by the node that initiated prior to the first time are determined to be complete. During the period of time after the first time and prior to performing the shutdown, a set of new processing requests are rejected by the node.

Abstract: A database system is operable to determine to generate a segment rebuild plan for rebuilding a first segment based on accessing first segment metadata for the first segment. A plurality of replicated part location data is determined for a plurality of parts of the first segment based on processing the first segment metadata and based on applying a deterministic segment part replica dispersal algorithm previously utilized to store the segment group. Nodes of the database system storing a corresponding plurality of sibling parts required to rebuild the plurality of parts of the first segment are determined based on the plurality of replicated part location data and based on storage location-to-node mapping data. The first segment is rebuilt based on applying the segment rebuild plan.

Abstract: A node of a database system is operable to determine, at a first time, to prepare for a shutdown. The shutdown of the node is performed at a second time that is a period of time after the first time based on the node delaying the shutdown until a plurality of currently running processes being run by the node that initiated prior to the first time are determined to be complete. During the period of time after the first time and prior to performing the shutdown, a set of new processing requests are rejected by the node.

Abstract: A database system operates by: determining a set of assigned segments based on data ownership information; generating a plurality of segment handles and a corresponding plurality of segment metadata for the set of assigned segments based on performing a segment activation step for the set of assigned segments; determining a first query for execution requiring access to a first segment of the set of assigned segments; and executing an IO operator of the first query based on loading the first segment by utilizing a corresponding one of the plurality of segment handles.

Abstract: A database system is operable to, during a first temporal period, facilitate execution of a first query to generate a first query resultant based on access to an initial set of segments. During a second temporal period after the first temporal period, an updated segment is generated based on determining to re-store corresponding column values of an initial segment via applying at least one storage optimization technique. During the second temporal period, execution of a second query is facilitated to generate a second query resultant via access to the initial segment. After the second temporal period, storage of the initial segment is replaced with storage of the updated segment. During a third temporal period after the second temporal period, execution of a third query is facilitated to generate a third corresponding query resultant via access to the updated segment.

Abstract: A database system is operable to execute a query transaction to generate addendum part data updating a segment A target storage node receives a plurality of sets of buffered rows and a plurality of flush requests. The target storage nodes each of a plurality of addendum parts in response to receiving a corresponding one of a plurality of flush requests. The target node assigns a plurality of version numbers to the plurality of addendum parts. A coordinator operator execution module commits only a final addendum part having a most recent version number as the addendum part data for the segment.

Abstract: A node of a database system is operable to determine, at a first time, to prepare for a shutdown. The shutdown of the node is performed at a second time that is a period of time after the first time based on the node delaying the shutdown until a plurality of currently running processes being run by the node that initiated prior to the first time are determined to be complete. During the period of time after the first time and prior to performing the shutdown, a set of new processing requests are rejected by the node.

Abstract: A database system is operable to communicate first system metadata to a plurality of nodes in a first temporal period, where each node of the plurality of nodes updates corresponding system configuration data as the first system metadata. At least one database function is performed in the first temporal period via the plurality of nodes operating in conjunction with the first system metadata. Updated system metadata is determined based on a first metadata change applied the first system metadata. The first metadata change is communicated to the plurality of nodes in a second temporal period, where each node further updates the corresponding system configuration data as the updated system metadata based on applying the first metadata change to the first system metadata. The at least one database function is performed in the second temporal period via the plurality of nodes operating in conjunction with the updated system metadata.