公开(公告)号：US20210149897A1

公开(公告)日：2021-05-20

申请号：US17093724

申请日：2020-11-10

Applicant: Daegu Gyeongbuk Institute of Science and Technology

Inventor： Min-Soo Kim ,  Yoon Min Nam ,  Sung Jin Lee

IPC: G06F16/2455 ,  G06F16/242 ,  G06F16/2453 ,  G06F16/22

Abstract: A method of processing database queries according to an embodiment of the disclosure includes the steps of acquiring an input query of a database, generating a join graph consisting of vertexes corresponding to the tables of the database and edges corresponding to join information among the tables, dividing the join graph into a plurality of subgraphs, and for the input query, generating an execution plan of a target query including N-ary join operators by using the plurality of subgraphs, optimizing the execution plan of the target query based on a cost model, acquiring a table sort algorithm of the N-ary join operators included in the target query based on an available size of a GPU or CPU memory, determining a sort order of one or more join columns included in the tables of the N-ary join operators, and based on the sort order of the one or more join columns, performing an operation for the plurality of subgraphs.

公开(公告)号：US11409746B2

公开(公告)日：2022-08-09

申请号：US17093724

申请日：2020-11-10

Applicant: Daegu Gyeongbuk Institute of Science and Technology

Inventor： Min-Soo Kim ,  Yoon Min Nam ,  Sung Jin Lee

IPC: G06F16/2455 ,  G06F16/22 ,  G06F16/242 ,  G06F16/2453

Abstract: A method of processing database queries according to an embodiment of the disclosure includes the steps of acquiring an input query of a database, generating a join graph consisting of vertexes corresponding to the tables of the database and edges corresponding to join information among the tables, dividing the join graph into a plurality of subgraphs, and for the input query, generating an execution plan of a target query including N-ary join operators by using the plurality of subgraphs, optimizing the execution plan of the target query based on a cost model, acquiring a table sort algorithm of the N-ary join operators included in the target query based on an available size of a GPU or CPU memory, determining a sort order of one or more join columns included in the tables of the N-ary join operators, and based on the sort order of the one or more join columns, performing an operation for the plurality of subgraphs.

公开(公告)号：US11068504B2

公开(公告)日：2021-07-20

申请号：US16327274

申请日：2017-01-11

Applicant: DAEGU GYEONGBUK INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Yoon Min Nam ,  Dong Hyoung Han ,  Min Soo Kim

IPC: G06F16/27 ,  G06F16/2455 ,  G06F16/22 ,  G06F16/2453

Abstract: A relational database storage method according to one embodiment generates a join graph including tables and edges based on either a database schema including referential constraints among database tables or a query workload containing a set of join predicates, classifies the type of tables based on the cost of a join operation between the tables included in the join graph, classifies the type of edges in the join graph on the basis of the type of the tables connected to each other by the edge, adds a virtual edge between two tables satisfying the indirect join condition, and generates a database partitioning scheme for the join graph based on the set of tables in the join graph and their type, the set of edges in the join graph and their type, and virtual edges.