,RelationalAlgebraOperationsfromSetTheory ,BinaryRelationalOperations:JOIN Copyright©2011RamezElmasriandShamkantNavatheRelationalCalculus ,Provideshigh-leveldeclarativelanguageforspecifyingqueriesintherelationalmodel ,Twotypes: ,Tuplerelationalcalculus:variablesrangeovertuples,and ...
13.7.4 Examples of Peano-tuple algebra queries Two examples of the use of the Peano-tuple algebra will be given in order to give a flavour of the way it may be used for solving spatial queries, for, respectively, a cadastre, a two-dimensional case, a geological problem, and a three-di...
Ratcl introduces a terminology and set of conventions which mini- mize the impedance mismatch caused by having databases added on instead of native persistence and querysupport, while Rasql takes this one step further to map standard SQL queries onto Ratcl. Working examples will be presented, ...
1 Introduction Let us start with two introductory examples to explain the problem setting of conditional ranking. Firstly, suppose that a number of persons are playing an online computer game. For many people it is always more fun to play against someone with similar skills, so players might ...
Load-Balancing Parallel Relational Algebra Sidharth Kumar(B) and Thomas Gilray University of Alabama at Birmingham, Birmingham, USA {sid14,gilray}@uab.edu Abstract. Relational algebra (RA) comprises a basis of important oper- ations, sufficient to power state-of-the-art reasoning engines for ...
Some examples of the most common queries that a developer might need are: (i) get an overview of the entities and the relationships between them, (ii) search variations with a set of properties, (iii) check all shared properties of all variations of a specific entity. The results of the...
An XML wrapper queries an XML document in an on-the-fly manner so that only parent nodes in the document that satisfy the query are extracted and then unnested. The parent nodes and
1997 Kluwer Academic Publishers. Manufactured in The Netherlands. Data Cube: A Relational Aggregation Operator Generalizing Group-By, Cross-Tab, and Sub-Totals ? JIM GRAY Gray@M SURAJIT CHAUDHURI SurajitC@M ADAM BOSWORTH AdamB@M ANDREW LAYMAN AndrewL@M DON REICHART DonRei@M MURALI VENKATRAO ...