Abstract: A system and method of the device may include receiving a commit statement that is part of a transaction, where the transaction is initiated by a client to be executed on the database system. In addition, the device may include validating the transaction in a pessimistic manner by placing a commit pause on data cells modified during the execution of the transaction, where the commit pause enables an atomicity of a distributed transaction commitment. The device may include returning an acknowledgment to the client that the transaction is committed, where the acknowledgment is returned upon validation of the transaction.

Abstract: In one general aspect, a method may include selecting eligible row-versions for inspection. The method may also include inspecting the selected row-versions, where the inspection results in a classification of eligible row-versions as unneeded or reliant. The method may furthermore include marking row-versions classified as unneeded as approved for immediate removal. The method may, in addition, include adding row-versions classified as reliant on cleaner structures. The method may moreover include upon detection of removal of all point-in-times (PiTs) related to a reliant row-version, deleting the reliant row-version, where the detection is performed by monitoring the cleaner structures. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

Abstract: A method and system for managing execution of database transactions are provided. The method includes receiving at least one statement that is a part of a transaction, wherein the transaction is initiated by a client to be executed on a database system; executing tasks included in each of the at least one received statement in an optimistic manner, wherein the received at least one statement is not a commit statement; and returning the client an acknowledgement that the transaction is committed, wherein the acknowledgement is returned upon validation of the transaction, wherein the transaction is validated in a pessimistic manner, and wherein the at least one received statement is a commit statement.

Abstract: A method and system for managing execution of database transactions by facilitating point-in-time image (PIT). The method comprises receiving at least one statement being part of a transaction, the transaction is initiated by a client to be executed on a distributed database system; sending a single request to a sequencer server (SEQ-server) to create at least one PiT, wherein the SEQ-server provides a logical timestamp counter (LTC) value as a timestamp of the PiT; upon creation of the at least one PiT, causing execution of the at least one statement, a PiT provides a state and content of committed data in the distributed database system; upon receiving a commit statement, performing a commitment process of the transaction, the commitment process is based on a commitment timestamp (CMTS) set by the SEQ-server based on an incremented value of the LTC; and returning an acknowledgment of the transaction commitment to the client.

Abstract: A method for cleaning unneeded row-versions in a distributed database system including a plurality of nodes are provided. The method comprising: receiving, by a node of the plurality of nodes, a stream of at least Point-in-Time (PiT) creation events and PiT removal events; receiving a list of committed transaction identifiers (IDs) of committed transactions executed by the distributed database system; inspecting row-versions in the distributed database system to identify unneeded row-versions that can be safely removed, wherein the inspection is performed in part using the stream of PiT creation events and PiT removal events, and the list of committed transaction IDs; and removing the unneeded row-versions identified by the inspection.

Abstract: A method and system for managing execution of database transactions are provided. The method includes receiving at least one statement that is a part of a transaction, wherein the transaction is initiated by a client to be executed on a database system; executing tasks included in each of the at least one received statement in an optimistic manner, wherein the received at least one statement is not a commit statement; and returning the client an acknowledgement that the transaction is committed, wherein the acknowledgement is returned upon validation of the transaction, wherein the transaction is validated in a pessimistic manner, and wherein the at least one received statement is a commit statement.

Abstract: A database system implementing a concurrency control protocol is provided. The database system includes a node connected through a network to a client; the node comprises: a storage for storing a plurality of data cells; one or more processors; and a memory, the memory containing instructions that, when executed by the one or more processors, configure the node to: receive at least one non-commit statement that is part of a transaction; execute locally tasks included in each of the at least one received statement in an optimistic manner allowing statements of other transactions to independently access same data cells in the database system being modified by tasks of the at least one received statement; and return the client an acknowledgment that the transaction is committed, the acknowledgment is returned upon validation of the transaction, wherein the transaction is validated in a pessimistic manner.