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 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 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 generate and a first plurality of column-formatted segments from a first plurality of rows. A query indicates parameters for generating a result set, and further indicating an instruction to store the result set. A query operator execution flow that includes a loading operator is generated. The query is executed based on accessing at least one of the first plurality of rows, processing the at least one of the first plurality of rows to generate a second plurality of rows as the result set, and executing the loading operator. At least one new column-formatted segment is from the second plurality of rows based on execution of the loading operator. The at least one new column-formatted segment is stored access in future query executions.