Query evaluation techniques for large databases

Query Optimization Techniques for XML Databases

Over the past few years, XML (eXtensible Mark-up Language) has emerged as the standard for information representation and data exchange over the Internet. This paper provides a kick-start for new researches venturing in XML databases field. We survey the storage representation for XML document, review the XML query processing and optimization techniques with respect to the particular storage in...

Query Evaluation for Distributed Heterogeneous Relational Databases

Evaluation of PTFs Developed From Large Databases for Iranian Soils To Predict SMRC

The majority of hydraulic processes under a natural condition in a field are carried out under unsaturated flow conditions. The soil moisture retention curve (SMRC) is the most important hydraulic characteristic of an unsaturated soil whose knowledge is of prime importance in soil-water studies such as soil conservation, soil erosion, land evaluation, soil reclamation, and water resources manag...

Query Evaluation on Probabilistic Databases

In this paper we consider the query evaluation problem: how can we evaluate SQL queries on probabilistic databases? Our discussion is restricted to single-block SQL queries using standard syntax, with a modified semantics: each tuple in the answer is associated with a probability representing our confidence in that tuple belonging to the answer. We present here a short summary of the research d...

Exploring Query Optimization Techniques in Relational Databases

In the modern era, digital data is considered as the more valuable asset of an organization, and the organizations assign more significance to it than the software and hardware assets. Database systems are computer-based record keeping systems, which have been developed to store data for efficient retrieval and processing. One particular approach is the relational databases in which all the inf...