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Which of the following indexing techniques are appropriate for data warehousing?
Bitmap indexes are widely used in data warehousing environments. The environments typically have large amounts of data and ad hoc queries, but a low level of concurrent DML transactions. For such applications, bitmap indexing provides: Reduced response time for large classes of ad hoc queries.
What is indexing in OLAP data?
INDEXING OLAP DATA: BITMAP INDEX. The bitmap indexing method is popular in OLAP products because it. allows quick searching in data cubes. The bitmap index is an alternative. representation of the record ID (RID) list.
Can You reorganize and rebuild indexes in the database?
You can remedy index fragmentation by reorganizing or rebuilding an index. For partitioned indexes built on a partition scheme, you can use either of these methods on a complete index or a single partition of an index. Rebuilding an index drops and re-creates the index.
Is it worth it to rebuild an index?
Rebuilding indexes, especially on a recurring schedule, is no longer important, and usually waste of resources. The only reason you would do this is for index fragementation where the entirety of the index pages are sequentially organized on a single rotating drive.
How does a database engine rebuild a ColumnStore index?
When rebuilding a columnstore index, the Database Engine reads all data from the original columnstore index, including the delta store. It combines data into new row groups, and compresses all row groups into columnstore. The Database Engine defragments the columnstore by physically deleting rows that have been marked as deleted.
Which is less resource intensive, index rebuild or reorganizing?
Reorganizing an index is less resource intensive than rebuilding an index. For that reason it should be your preferred index maintenance method, unless there is a specific reason to use index rebuild.