An intention of MapReduce Sets for Reduce side join part file expressions analysis has to suggest criteria how Reduce side join part file expressions in Reduce side join part file data can be defined in a meaningful way and how they should be compared. Similitude based MapReduce Sets for Reduce side join part file Expression Analysis and MapReduce Sets for Assignment is expected to adhere to fu...

A join-index is a data structure used for processing join queries in databases. Join-indices use precomputation techniques to speed up online query processing and are useful for data sets which are updated infrequently. The I/O cost of join computation using a join-index with limited buffer space depends primarily on the page-access sequence used to fetch the pages of the base relations. Given ...

A Join Index is a data structure used for processing join queries in databases. Join indices use pre-computation techniques to speed up online query processing and are useful for data-sets which are updated infrequently. The cost of join computation using a join-index with limited buuer space depends primarily on the page-access sequence used to fetch the pages of the base relations. Given the ...

Not only in deductive databases, logic programming, and constraint satisfaction problems but also in object bases where each single dot in a path expression corresponds to a join, the optimizer is faced with the problem of ordering large numbers of joins. This might explain the renewed interest in the join ordering problem. Although many join ordering techniques have been invented and benchmark...

One of the main features of XQuery compared to traditional query languages like SQL, is that it preserves the input order—unless specified otherwise. As a consequence, order-preserving algebraic operators are needed to capture the semantics of XQuery correctly. One important algebraic operator is the orderpreserving join. The order-preserving join is associative but, in contrast to the traditio...

This article presents an approach of the cost model used in join optimization. The search space is determined through transformations on the query blocks, depending on the selection predicate. Different implementations of the JOIN operator are taken into account for cost evaluation of the execution plans. Subject Classification: 168P15.

Index selection is one of the most important decisions to take in the physical design of relational data warehouses. Indices reduce significantly the cost of processing complex OLAP queries, but require storage cost and induce maintenance overhead. Two main types of indices are available: mono-attribute indices (e.g., B-tree, bitmap, hash, etc.) and multi-attribute indices (join indices, bitmap...