First Advisor

Eugster, Ernest

Thesis Committee Member(s)

Ina, Donald


College for Professional Studies

Degree Name

MS Software Engineering and Database Technologies


School of Computer & Information Science

Document Type

Thesis - Open Access

Number of Pages

461 pages


Database systems use optimizers on queries to select execution pathways that are supposed to provide optimal performance. The Oracle database version of this technology is called the Cost Based Optimizer (CBO). Researchers have studied whether Oracle optimizer estimates could be correlated to execution speeds with a high degree of confidence, but have found that correlating optimizer cost estimates with actual execution speed to be problematic and unreliable. If possible, however, such correlations would be helpful to developers who are tasked with query creation and optimization. Although much has been written on databases, the academic literature on optimizers was sparse. To fill the gap, this researcher developed a quantitative research methodology to test query optimization on an Oracle 11g database. Correlations between cached, non-cached, partitioned and non-partitioned table structures and indexes were performed. The findings suggest that confident correlations between optimizer cost estimates and execution speeds are not yet possible. Suggestions for further research were provided.

Date of Award

Summer 2013

Location (Creation)

Colorado (state); Denver (county); Denver (inhabited place)

Rights Statement

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