公开(公告)号：US11429584B2

公开(公告)日：2022-08-30

申请号：US17037484

申请日：2020-09-29

Applicant: SAP SE

Inventor： Juchang Lee ,  KiYong Lee ,  Nosub Sung

IPC: G06F16/20 ,  G06F16/22 ,  G06F16/27 ,  G06F16/23 ,  G06F16/2455

Abstract: Technologies are described for improving the performance of distributed database systems. The technologies provide suggested table distributions that can reduce the performance overhead associated with database operations that involve multiple nodes, and can provide more even distribution of computing resource use. In a particular example, a method includes minimizing a scoring function that includes a plurality of performance metrics, at least a portion of the metrics being associated with a weight. Candidate table distributions can be analyzed in an iterative manner to determine a lowest-score distribution. A final table distribution can be output, such as to a user.

公开(公告)号：US11379486B2

公开(公告)日：2022-07-05

申请号：US16713929

申请日：2019-12-13

Applicant: SAP SE

Inventor： Ruediger Karl ,  Mihnea Andrei ,  Juchang Lee ,  Stefan Baeuerle ,  Seyeong Bae ,  Joo Yeon Lee

IPC: G06F7/00 ,  G06F17/00 ,  G06F16/2455 ,  G06F16/23

Abstract: Techniques and solutions are described for implementing virtual table schemas. A virtual table schema includes a logical pointer that is used to target a table that includes data and is defined according to the virtual table schema. Values assigned to the logical pointer can be used to target tables at different locations, such as in-memory storage or in dynamic storage of a database management system. The dynamic storage includes an in-memory buffer cache and persistent storage. The logical pointer can be updated to point to the in-memory storage or the dynamic storage, including based on use statistics. Similarly, a table having data for the virtual table can be transitioned between the in-memory buffer cache and the persistent storage, including based on use statistics for the virtual table. A value for the logical pointer can be updated when the table is transferred between the in-memory buffer cache and the dynamic storage.

公开(公告)号：US11379323B2

公开(公告)日：2022-07-05

申请号：US16704727

申请日：2019-12-05

Applicant: SAP SE

Inventor： Kyu Hwan Kim ,  Deok Hoe Kim ,  Beomsoo Kim ,  Juchang Lee ,  Werner Thesing ,  Christoph Roterring

IPC: G06F11/00 ,  G06F11/14 ,  G06F16/23 ,  G06F16/27 ,  G06F11/20 ,  G06F11/30 ,  G06F11/07

Abstract: A computer implemented method is provided for determining a delay between a first database and an associated replicated database by replicating transactions of the first database in the replicated database, determining a delay between the two databases based on a commit timestamp from the first database and a timestamp associated with the commit transaction becoming visible in the replicated database. Then, after a predefined period of time has elapsed since replicating the commit transaction, determining a second delay based on a timestamp associated with a heartbeat log and a replicated database system time. And, selectively determining to execute or deny a statement received by the replicated database based on the second delay. Related apparatus, systems, techniques and articles are also described.

公开(公告)号：US20220179860A1

公开(公告)日：2022-06-09

申请号：US17678720

申请日：2022-02-23

Applicant: SAP SE

Inventor： Chul Won Lee ,  Juchang Lee ,  Myunggon Park ,  Wonyoung Kwak ,  Jeong Hee Won ,  Ki Hong Kim ,  Kyu Hwan Kim ,  Beomsoo Kim

IPC: G06F16/2453 ,  G06F16/11 ,  G06F16/13 ,  G06F16/17 ,  G06F16/21

Abstract: Technologies are described for facilitating data workload capture, workload replay, and comparing the performance of a plurality of database systems. A plurality of requests for database operations are received from one or more database clients. The requests for database operations are executed. For the plurality of requests for database operations, execution context information is generated for a plurality of execution contexts. For the plurality of requests for database operations, a plurality of performance measures are generated. The execution context information and the performance measures are stored in a workload capture store, such as a file. The workload capture file is useable to replay the captured workload at a second database system using at least a portion of the execution context information and at least a portion of the performance measures.

公开(公告)号：US11321344B2

公开(公告)日：2022-05-03

申请号：US16713850

申请日：2019-12-13

Applicant: SAP SE

Inventor： Ruediger Karl ,  Mihnea Andrei ,  Juchang Lee ,  Stefan Baeuerle ,  Seyeong Bae ,  Joo Yeon Lee

IPC: G06F16/25 ,  G06F16/23 ,  G06F16/22 ,  G06F16/2455 ,  G06F16/21

Abstract: Techniques and solutions are described for implementing virtual table schemas. A virtual table schema includes a logical pointer that is used to target a table that includes data and is defined according to the virtual table schema. Values assigned to the logical pointer can be used to target tables at different locations, such as in a federated database system or in a cache of a database management system of a central computing system. When data associated with the virtual table is requested, or prior to receiving the request, the data can be stored in a table in the cache. The logical pointer can be updated to reference the cache. If the cache is full, the table can be removed from the cache, and the logical pointer can be updated to reference a table at the federated database system.

公开(公告)号：US11263236B2

公开(公告)日：2022-03-01

申请号：US16686827

申请日：2019-11-18

Applicant: SAP SE

Inventor： Juchang Lee ,  Seoyoon Choi ,  Eunsang Kim ,  Kyu Hwan Kim ,  Joo Yeon Lee ,  Hyoung Jun Na

IPC: G06F16/27 ,  G06F16/23 ,  G06F16/22

Abstract: RTR of a database transaction to a replica table may include receiving replication and transaction commit log entries (representing a database transaction). The replication log entry has a row-ID value, and the row at the replica table has a row-ID value. The replication log entry may be dispatched to a parallel log replayer and the associated transaction commit log entry to a transaction commit log replayer. The row-ID values may be compared, and the replication log entry is replayed at the parallel log replayer based on the comparison. The database transaction may then be committed to the replica table by replaying the associated transaction commit log entry at the transaction log replayer, wherein the database transaction is associated with row-level parallel replay having transactional consistency and DDL replication and reconstruction of a DDL statement at the replica system is associated with one or multiple metadata update log entries.

公开(公告)号：US11137911B2

公开(公告)日：2021-10-05

申请号：US16503122

申请日：2019-07-03

Applicant: SAP SE

Inventor： Yong Sik Kwon ,  Jaeyun Noh ,  Juchang Lee ,  Ji Hoon Jang ,  Sang Kyun Cha

IPC: G06F3/06 ,  G06F9/46 ,  G06F9/54 ,  G06F9/44 ,  G06F9/48 ,  G06F9/52 ,  G06F13/16 ,  G06F9/445 ,  G06F9/4401

Abstract: Technologies are described for restarting an application while maintaining data in memory (e.g., using shared memory). For example, shared memory can be associated with an application. The shared memory can also be associated with a holder process to maintain the shared memory from the time the application stops to the time the application starts again. When the application starts, the shared memory can be associated with the started application. In addition, restart of in-memory databases can be provided using shared memory. For example, in-memory data can be maintained when a database process or database management system stops and starts (e.g., during a restart).

公开(公告)号：US20210089552A1

公开(公告)日：2021-03-25

申请号：US16713194

申请日：2019-12-13

Applicant: SAP SE

Inventor： Ruediger Karl ,  Mihnea Andrei ,  Juchang Lee ,  Stefan Baeuerle ,  Seyeong Bae ,  Joo Yeon Lee

IPC: G06F16/27 ,  G06F16/21 ,  G06F16/2455 ,  G06F16/22

Abstract: Techniques and solutions are described for implementing virtual table schemas. A virtual table schema includes a logical pointer that is used to target a table that includes data and is defined according to the virtual table schema. Values assigned to the logical pointer can be used to target tables at different locations, such as tables located in a remote database system, replica tables containing data replicated from a table in a remote database system, or cached table data. Replica tables targeted by a logical pointer of a virtual table schema can have various locations, such as being located in main memory of a database system, being located in a dynamic storage system, or being located in a data lake. Replica tables can be transferred between locations based on various criteria.

公开(公告)号：US10860612B2

公开(公告)日：2020-12-08

申请号：US16014935

申请日：2018-06-21

Applicant: SAP SE

Inventor： Juchang Lee ,  Hyoung Jun Na ,  Kyu Hwan Kim ,  Deok Hoe Kim ,  Chang Gyoo Park

IPC: G06F16/27 ,  G06F11/14 ,  G06F3/06 ,  G06F16/17 ,  G06F16/182 ,  G06F16/2453 ,  G06F16/2455

Abstract: Disclosed herein are system, method, and computer readable device embodiments for parallel replication of databases across row-store and column-store table formats. An embodiment operates by maintaining a replication log and a storage-level recovery log formatted according to separate respective log formats, logging a record-level SQL execution result, and replicating at least one database table from a primary server to at least one replica server. The primary server and the at least one replica server may each be configured to store data according to one table format of a row-store table format and a column-store table format, such that the primary server's table format is different from the at least one replica server's table format.

公开(公告)号：US10795881B2

公开(公告)日：2020-10-06

申请号：US14975365

申请日：2015-12-18

Applicant: SAP SE

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

IPC: G06F16/27 ,  G06F16/23 ,  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.