Products | Versions |
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TIBCO Data Virtualization | - |
Statistic Gathering Approaches – Column boundary vs. Table Boundary
The configuration and usage of cardinality statistics is described in "Creating Cardinality Statistics for Cost-Based Optimization" section of Tibco Data Virtualization User Guide. Refer to the topic on Creating Cardinality Statistics on a View, for information on how this panel is configured and used.
Approach
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Computation
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Effort to infer information
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Column Boundary
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High
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It builds histograms for each column. So it’s very detailed and granular but takes the most effort to infer the information as well.
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Table Boundary
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Least
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It returns the number of total rows and distinct rows per table. Very easy and most direct.
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