Abstract: This invention relates to a method which provides, showing as well the relevant documents to the user even if the said documents that are closely related to the subject do not contain the keywords that are entered for search in their content, by analyzing citation contexts of every document in a data pool containing documents that are citing or linking to at least one document. In an alternative embodiment of this method, in the case when the documents cited by using the entered keywords are cited by other documents using other keywords, these said other keywords are considered as similar terms and the search is conducted as well by including these said similar terms.

Abstract: A database system includes a query planner with instructions executed by a processor to generate a logical plan tree. Each node of the logical plan tree is a distributed relational algebra operator. Each child node of the logical plan tree produces results processed by a parent node. The logical plan tree includes a distributed relational operator that reparations tuples of results that are at least 1 GB on a dimension and regroups the tuples on the dimension to avoid broadcasting the tuples between machines and thereby avoid consumption of network bandwidth associated with broadcasting the tuples. The logical plan tree is modified according to algebraic transformation rules. The logical plan tree is mapped to distributed query execution primitives. The distributed query execution primitives are processed on machines storing partitions of a distributed database table.

Abstract: This invention relates to a method which provides, showing as well the relevant documents to the user even if the said documents that are closely related to the subject do not contain the keywords that are entered for search in their content, by analyzing citation contexts of every document in a data pool containing documents that are citing or linking to at least one document. In an alternative embodiment of this method, in the case when the documents cited by using the entered keywords are cited by other documents using other keywords, these said other keywords are considered as similar terms and the search is conducted as well by including these said similar terms.

Abstract: A database system includes a query planner with instructions executed by a processor to generate a logical plan tree. Each node of the logical plan tree is a distributed relational algebra operator. Each child node of the logical plan tree produces results processed by a parent node. The logical plan tree includes a distributed relational operator that reparations tuples of results that are at least 1 GB on a dimension and regroups the tuples on the dimension to avoid broadcasting the tuples between machines and thereby avoid consumption of network bandwidth associated with broadcasting the tuples. The logical plan tree is modified according to algebraic transformation rules. The logical plan tree is mapped to distributed query execution primitives. The distributed query execution primitives are processed on machines storing partitions of a distributed database table.