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Part of record keeping when overflow occurs

IP.com Disclosure Number: IPCOM000240026D
Publication Date: 2014-Dec-24
Document File: 4 page(s) / 99K

Publishing Venue

The IP.com Prior Art Database

Abstract

It is very common that when the table contains variable length columns, record updating might cause record overflow. When overflow occurs, database would leave a point in the position. When we search for the record which is already overflow, database would search the position for the record to get the point and then get the record by the address. If the record meet overflow several times, database should search the record several times also. This would reduce the performance for getting record. We propose a system and method to reduce the second page search as most to increase the search page performance.

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Part of record keeping when overflow occurs

It is very common that when the table contains variable length columns, record updating might cause record overflow. When overflow occurs, database would leave a point in the position. When we search for the record which is already overflow, database would search the position for the record to get the point and then get the record by the address. If the record meet overflow several times, database should search the record several times also. This would reduce the performance for getting record.

As shown as below, in the original, the record is arranged in order.

When the record 2 is updated and the space is not large enough to hold the whole record , so the record 2 would be moved to another space, and the pointer would be left to link to the new record address.

When the record is overflow, there might be space to keep part of the records. Our method is that we keep some columns in the original position and also a pointer to the new position. Database would decide which columns would be kept by last frequency and the space usage.

When the record is overflow, before moving the whole record to the new address, the database would balance the access frequency and space usage. The basic elementary database considers is the column relation group instead of the single column. Usually, some columns might always appear together. Database would calculate a cost which make the queries which find record twice at least. We also design a quickly method when there is no columns selected for left.

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1. Enable the feature by special register, PARM or other methods


For this new feature, we could disable or enable it by special register, PARM or other methods. Users have the authority to choose by their desire.


2. Overflow occur during update


Overflow would happen during update when the new record's length increases. It might happen even when the record's length add one longer.

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3. Check the columns could be kept


Database would keep part of columns inline to reduce second page search. Database would decide which column sho...