Early Separation of Filter and Re nement
نویسندگان
چکیده
The spatial query has been processed in two steps, the lter step and the reenement step, due to a large volume and high complexity of the spatial data. However, this approach has been considered only in the query execution phase after completing the query optimization phase. This paper presents query optimization strategies which take the characteristics of spatial databases into account. The rst strategy is the separation of lter and reenement steps not in the query execution phase but in the query optimization phase. As the second strategy, several reenement operations can be combined in processing a complex query, and as the third strategy several lter operations can also be combined. We call the optimization technique utilizing these strategies the Early Separated Filter And Reenement(ESFAR). This paper also presents a rule-based optimization technique for ESFAR.
منابع مشابه
Spatial Query Optimization Utilizing Early Separated Filter and Refinement Strategy
| Due to the high complexity and large volume of spatial data, a spatial query is usually processed in two steps, called the lter step and the re nement step. However, the two-step processing of the spatial query has been considered locally in one spatial predicate evaluation at the query execution level. This paper presents query optimization strategies which exploit the two-step processing of...
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