由于StarRocks 是基于MPP 架构的大数据场景中的数据引擎,因此不同于传统的 DBMS,其突破了传统 DBMS 对 Low cardinality 的限制,可以针对列值种类更多的情况进行 Bitmap Indexing 并从中受益。下面的示例语句就是 StarRocks 引擎基于用户唯一编码user_id进行的 Bitmap Indexing 提供的官方示例: 主键表 (Primary Key T...
The bit is the smallest unit used to represent data that has 0 or 1 as its values. It is the bit arrays used to answer queries by performing bitwise logical operations on bitmaps. Indexing refers to a data structure that organizes data based on a specific schema. This bitmap indexing tech...
What is big data in data warehousing? What is indexing in big data? Why is a search engine a big data application? What are the differences of storage architecture between DBMS and OODBMS? Why is data security important? What makes an application a big data application? Why zip a folder?
database indexingtree data structures/ data warehousetree based indexesbitmap indexesmaterialized viewsindex structuresclassification treesscatter diagramaggregated data/ C6160Z Other DBMS C6120 File organisation C4250 Database theory C1160 Combinatorial mathematicsData warehouses are used to store large ...
the use of bitmap indexing [8, 9, 10]. Bitmap manipulation tech- niques have already been used in some commercial products [12] to speed up query processing: a notable example is Model 204, a pre-relational DBMS from Computer Corporation of America ...
Filed under:bitmaps,Indexing,Oracle,Performance,Troubleshooting— Jonathan Lewis @ 12:15 pm GMT Jan 19,2015 In anearlier (not very serious) postabout count(*) I pointed out how the optimizer sometimes does a redundant“bitmap conversion to rowid”when counting. In the basic count(*) example ...