Databases Reference
In-Depth Information
Figure 8.6
MDC performance on POPS schema.
Example 3: MDC Table with Three Dimensions
(Nation, Year, Product ID)
DELETE FROM table WHERE year = 1992 and product_id = 1
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MDC will enable faster delete along cell or slice boundaries.
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The query compiler determines if the DELETE statement qualifies for roll-out.
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There is no need for a specialized statement or command.
8.4
Examples of Queries Benefiting from MDC
The following examples describe SQL queries that can take advantage of MDC. In
these examples we have a multidimensionally clustered table MY_TABLE with cluster-
ing dimensions DATEOFSALE, COLOR, and REGION. Nonclustering columns in
the tables include the “sales” column, a numeric field. In these scenarios, consider
