US 11,874,812 B2
Optimizing performance using a metadata index subtable for columnar storage
Snigdha Prasad, Hyderabad (IN); Dinesh Chengalpatu, Hyderabad (IN); Arnab Roy, Hyderabad (IN); Sama Rajender Reddy, Hyderabad (IN); Karthik Sai Vakkalagadda, Vizag (IN); and Venkata Sai Prakash Reddy Sangu, Guntur (IN)
Assigned to Teradata US, Inc., San Diego, CA (US)
Filed by Teradata US, Inc., San Diego, CA (US)
Filed on Aug. 24, 2021, as Appl. No. 17/410,655.
Claims priority of provisional application 63/132,599, filed on Dec. 31, 2020.
Prior Publication US 2022/0207011 A1, Jun. 30, 2022
Int. Cl. G06F 16/22 (2019.01); G06F 16/2455 (2019.01); G06F 16/2457 (2019.01); G06F 16/28 (2019.01)
CPC G06F 16/221 (2019.01) [G06F 16/2282 (2019.01); G06F 16/24554 (2019.01); G06F 16/24573 (2019.01); G06F 16/284 (2019.01)] 15 Claims
OG exemplary drawing
 
1. A computer-implemented method, comprising:
executing a relational database management system (RDBMS) in a computer system, wherein:
the RDBMS manages a relational database comprised of at least one column-partitioned base table storing data;
column values from at least one column of the column-partitioned base table are stored in one or more partitions comprised of one or more containers spread across one or more data blocks;
metadata comprising summarized information about the column values in the containers is stored in a metadata index subtable, wherein the metadata index subtable is comprised of metadata information for accessing the partitions, containers and data blocks, which includes a partition identifier for the column-partitioned base table, a row identifier for the metadata index subtable that is also a container identifier for the column-partitioned base table, a minimum column value, and a maximum column value; and
a query with a filtering condition on a column of the column-partitioned base table is applied to the metadata index subtable before the column-partitioned base table is accessed, so that only qualified containers and data blocks are accessed, and unqualified containers and data blocks are eliminated, when responding to the query.