Bitmap Indexing in DBMS Bitmap Index vs. B-tree Index low cardinality

1、

Similarly let us assume that the Job of the Employees is divided into 4 categories only i.e Manager, Analyst, Clerk, and Salesman. Such columns are called columns with low cardinality. 

 2、

 

 

 SELECT * 
        FROM Employee 
            WHERE New_Emp = "No" and Job = "Salesperson";

 

Bitmap Indexing in DBMS - GeeksforGeeks https://www.geeksforgeeks.org/bitmap-indexing-in-dbms/

Bitmap Index vs. B-tree Index: Which and When? https://www.oracle.com/technical-resources/articles/sharma-indexes.html

 

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