| 摘要 |
A plurality of table-formatted data can be joined at a high speed without requiring use of a large capacity of memory. Each table-formatted data is divided into one or more information blocks consisting of a value list containing item values in the order of item value numbers corresponding to t he item values belonging to a particular item and a pointer array containing pointer values specifying the item value numbers in the order of uniquely- defined record numbers. When joining a plurality of table formats, equivalen t items between the table-formatted data are found and the value lists contain ed in the information block concerning the equivalent items are compared and th e two value lists are made equivalent. After this, data of one of the table formats is sorted according to a key item and by using the array obtained in this process, calculation is performed to obtain addresses indicating storag e positions of record numbers of the table-formatted data and the other table- formatted data. By using the calculated addresses, joined table-formatted da ta is displayed.
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