| 摘要 |
A method for performing disjunctive single-index access on a database is disclosed. The method includes a query engine determining whether a first OR predicate and a second OR predicate map to a shared index. Responsive to the query engine determining that the first OR predicate and the second OR predicate map to the shared index, the first OR predicate and the second OR predicate are ordered in an ascending sequence. A first range of the first OR predicate is queued. A first row of the shared index is probed for the first range of the first OR predicate. Whether the first row is disqualified by the first OR predicate is determined. Responsive to determining that the first row is not disqualified by the first OR predicate, the row is reported in a result reporting structure. Responsive to determining that the row is disqualified by the first OR predicate, whether the first range of the first OR predicate overlaps a second range of the second OR predicate is determined, and, responsive to determining that the first range of the first OR predicate overlaps the second range of the second OR predicate, the row is checked against second range of the second or predicate.
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