公开(公告)号：US20160371319A1

公开(公告)日：2016-12-22

申请号：US14871765

申请日：2015-09-30

Applicant: SAP SE

Inventor： Chang Gyoo Park ,  Deok Koo Kim ,  Kyu Hwan Kim ,  Juchang Lee

IPC: G06F17/30

CPC classification number: G06F17/30578 ,  G06F11/1451 ,  G06F17/30362 ,  G06F17/30377 ,  G06F17/30545 ,  G06F17/30598 ,  G06F17/30864

Abstract: Technologies are described for performing synchronization within a database environment. A source host stores multiple database tables and a replica host stores copies of the multiple database tables. During synchronization, replication log replay is blocked at the replica node, and a multithreaded process locks the multiple database tables of the source hosts, reactivates replication log generation for each of the multiple database tables, and then unlocks the database tables. A synchronization timestamp is acquired and used to synchronize the multiple database tables with the copies of the multiple database tables. After synchronization, replication log replay is reactivated at the replica host for the copies of the multiple database tables.

Abstract translation: 描述了在数据库环境中执行同步的技术。 源主机存储多个数据库表，副本主机存储多个数据库表的副本。 在同步期间，复制日志重播在副本节点被阻止，多线程进程锁定源主机的多个数据库表，重新启动每个多个数据库表的复制日志生成，然后解锁数据库表。 获取同步时间戳并用于将多个数据库表与多个数据库表的副本同步。 同步之后，复制日志重放在副本主机上重新激活，以获取多个数据库表的副本。

公开(公告)号：US11327958B2

公开(公告)日：2022-05-10

申请号：US17005085

申请日：2020-08-27

Applicant: SAP SE

Inventor： Juchang Lee ,  Chang Gyoo Park ,  Kyu Hwan Kim ,  Hyoung Jun Na ,  Deok Koo Kim ,  Joo Yeon Lee

IPC: G06F16/00 ,  G06F16/23 ,  G06F16/27 ,  G06F11/14

Abstract: Technologies are described for performing replication of data within a database environment having a source node and a replica node. The source node executes a database operation on at least one database table stored by the source node. The source node asynchronously sends the database operation to the replica node. A prepare commit request is synchronously sent from the source node to the replica node. The source node receives a synchronous precommit acknowledgement from the replica node. The precommit acknowledgement indicates that the database operation was executed at the replica node. The source node commits a transaction associated with the database operation.

公开(公告)号：US10990610B2

公开(公告)日：2021-04-27

申请号：US16376963

申请日：2019-04-05

Applicant: SAP SE

Inventor： Chang Gyoo Park ,  Deok Koo Kim ,  Kyu Hwan Kim ,  Juchang Lee

IPC: G06F17/00 ,  G06F16/27 ,  G06F16/28 ,  G06F16/951 ,  G06F16/23 ,  G06F16/2458 ,  G06F11/14

Abstract: Technologies are described for performing synchronization within a database environment. A source host stores multiple database tables and a replica host stores copies of the multiple database tables. During synchronization, replication log replay is blocked at the replica node, and a multithreaded process locks the multiple database tables of the source hosts, reactivates replication log generation for each of the multiple database tables, and then unlocks the database tables. A synchronization timestamp is acquired and used to synchronize the multiple database tables with the copies of the multiple database tables. After synchronization, replication log replay is reactivated at the replica host for the copies of the multiple database tables.

公开(公告)号：US10761946B2

公开(公告)日：2020-09-01

申请号：US15430091

申请日：2017-02-10

Applicant: SAP SE

Inventor： Christian Bensberg ,  Steffen Geissinger ,  Juchang Lee ,  Chang Gyoo Park ,  Kyu Hwan Kim ,  Deok Koo Kim

IPC: G06F11/14

Abstract: Technologies are described for facilitating database system recovery in a distributed database environment having a master node and at least one slave node. The master node maintains an in-memory reference that includes transaction identifiers and their corresponding commit identifiers. When a slave node requests that a commit identifier be assigned to a transaction, the transaction and commit identifiers for the transaction are added to the in-memory reference. The commit identifier is sent by the master node to the slave node. The slave node writes a log entry to a commit log that includes the transaction identifier and the assigned commit identifier. If the database system is interrupted before the slave node writes the commit log entry, the slave node can request the commit identifier for the transaction from the master node, which retrieves the identifier from the in-memory reference.

公开(公告)号：US10554771B2

公开(公告)日：2020-02-04

申请号：US16362286

申请日：2019-03-22

Applicant: SAP SE

Inventor： Chang Gyoo Park ,  Juchang Lee ,  Kyu Hwan Kim ,  Chul Won Lee ,  Myunggon Park ,  Eunjin Song ,  Nosub Sung

IPC: H04L29/06 ,  H04L29/08 ,  G06F16/20 ,  G06F16/2455 ,  H04L12/747

Abstract: Technologies are described for facilitating replay of requests for database operations. A plurality of requests for database operations are received. Each of the plurality of requests includes a type, an access unit identifier, and a chronological identifier. Execution dependencies are determined between the plurality of requests based on the type, access unit identifier, and chronological identifier of each of the plurality of requests. The execution dependencies are stored.

公开(公告)号：US20190303470A1

公开(公告)日：2019-10-03

申请号：US15944429

申请日：2018-04-03

Applicant: SAP SE

Inventor： Juchang Lee ,  Chang Gyoo Park ,  Hyoung Jun Na

IPC: G06F17/30

Abstract: Techniques are described for use in database and data management systems to efficiently capture and replicate changes that occur in database tables. The changes are captured in a transaction-consistent order, and in a format that may easily be searched and accessed using common relational queries.

公开(公告)号：US20190303468A1

公开(公告)日：2019-10-03

申请号：US15944447

申请日：2018-04-03

Applicant: SAP SE

Inventor： Chang Gyoo Park

IPC: G06F17/30

Abstract: Lock table management is provided for a lock manager of a database system, in which lock management is provided in a manner that is fast and efficient, and that conserves processing, memory, and other computational resources. For example, the lock table management can use a hashmap in which keys and values are stored in separate arrays, which can be loaded into separate CPU cache lines.

公开(公告)号：US10360146B2

公开(公告)日：2019-07-23

申请号：US15231566

申请日：2016-08-08

Applicant: SAP SE

Inventor： Juchang Lee ,  Chang Gyoo Park ,  Jaeyun Noh ,  Sung Heun Wi

IPC: G06F12/02 ,  G06F16/23 ,  G06F3/06 ,  G06F3/05

Abstract: Technologies for performing garbage collection in database systems, such as multi-version concurrency control (MVCC) database systems, are described. For example, different garbage collection techniques can be used separately or in various combinations, including interval garbage collection, group garbage collection, table garbage collection, and combinations. For example, a particular type of combination, called hybrid garbage collection, uses technique from interval garbage collection and group garbage collection, or from interval, group, and table garbage collection.

公开(公告)号：US10235440B2

公开(公告)日：2019-03-19

申请号：US14977427

申请日：2015-12-21

Applicant: SAP SE

Inventor： Juchang Lee ,  Chang Gyoo Park ,  Kyu Hwan Kim

IPC: G06F17/30

Abstract: Technologies are described for facilitating transaction processing within a database environment having first, second, and third database system nodes. In the database system, the first database system node receives from the second database system node a request to precommit a first database transaction. The first database system node stores information for the first database transaction that includes an indication that the second database system node coordinates the committing of the first database transaction. The first database system node receives from the third database system node a request to precommit a second database transaction. The first database system node stores information for the second database transaction that includes an indication that the third database system node coordinates the committing of the second database transaction.

公开(公告)号：US20180336258A1

公开(公告)日：2018-11-22

申请号：US15601008

申请日：2017-05-22

Applicant: SAP SE

Inventor： Juchang Lee ,  Chang Gyoo Park ,  Hyejeong Lee ,  Kyu Hwan Kim ,  Mihnea Andrei

IPC: G06F17/30

CPC classification number: G06F16/273 ,  G06F11/36 ,  G06F16/219 ,  G06F16/2358 ,  G06F16/2379 ,  G06F16/2455

Abstract: An oldest version timestamp is received from a first database. A current commit timestamp is received from a second database configured to asynchronously replicate the first database. The current global commit timestamp corresponds to a commit transaction executed in the first database and subsequently replicated in the second database. A first test query is then issued to the second database including a request for a current timestamp of the second database. A second test query is issued to the primary database requesting records associated with a target update version that has a target timestamp equal to the current snapshot timestamp. A determination is then made that a first return associated with the first test query and a second return associated with the second test query are identical indicating a successful validation. Related apparatus, systems, techniques and articles are also described.