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
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...
data warehousesdatabase indexingquery processing/ data mining approachefficient selection bitmap join indexdata warehousegreedy algorithmattribute candidatesquery processing cost/ C7250R Information retrieval techniques C6130 Data handling techniques C6160Z Other DBMS...
1000 DBMS MCQs Relational Model SQL : Queries, Constraints & Triggers Relational Algebra Database Systems Design & Implementation Normalization Database Programming Techniques Storage & File Structures Indexing & Hashing Query Processing Techniques Transactions Concurrency Control Recovery System Best Reference ...
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 an earlier (not very serious) post about count(*) I pointed out how the optimizer sometimes does a redundant “bitmap conversion to rowid” when counting. In the basic count(*) ...
Tree Based Indexes Versus Bitmap Indexes: A Performance Study - Jurgens, Lenz - 2001 () Citation Context ...each attribute in the new database is an exact value of one item in original system, and each attribute value is either 1 or 0,expressing if it is present there is a „1‟...