Can control ll factor on pages a note on order order

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Unformatted text preview: n of records, and we want to create a B+ tree on some field, doing so by repeatedly inser6ng records is very slow. •  Bulk Loading can be done much more efficiently. •  Ini2aliza2on: Sort all data entries, insert pointer to first (leaf) page in a new (root) page. Root 3* 4* Sorted pages of data entries; not yet in B+ tree 6* 9* 10* 11* 12* 13* 20* 22* 23* 31* 35* 36* 38* 41* 44* Bulk Loading (Contd.) Root •  Index entries for leaf pages always entered into right ­most index page just above leaf level. When this fills 3* up, it splits. (Split may go up right ­most path to the root.) •  Much faster than repeated inserts, especially when one considers locking! 10 6 4* 3* 4* 6* 9* 20 12 23 20 10 6* 9* not yet in B+ tree 10* 11* 12* 13* 20* 22* 23* 31* 35* 36* 38* 41* 44* Root 6 Data entry pages 35 12 Data entry pages not yet in B+ tree 35 23 38 10* 11* 12* 13* 20* 22* 23* 31* 35* 36* 38* 41* 44* Summary of Bulk Loading •  Op6on 1: mul6ple inserts. –  –  Slow. Does not give sequen6al storage of leaves. •  Op6on 2: Bulk Loading –  –  –  –  Has advantages for concurrency control. Fewer I/Os during build. Leaves will be stored sequen6ally (and linked, of course). Can control “fill factor” on pages. A Note on `Order’ •  Ord...
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This document was uploaded on 03/12/2014 for the course CSCI 165B at UC Davis.

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