Ph.D. in Computer Sciences, University of Wisconsin-Madison, August 2000.

Thesis: Techniques for Partial Query Evaluation

Advisor: Prof. Raghu Ramakrishnan

GPA: 3.96

M.S. in Computer Sciences, University of Wisconsin-Madison, May 1996

M.S. in Physics, University of Wisconsin, Madison, May 1995. (GPA: 4.0)

B.S. in Physics, University of Zagreb, Croatia, July 1992. (GPA: 3.9)

• Principal Member of Technical Staff, Siebel Systems, Acquired by Oracle (2/16/2005 - Present). Designed and implemented following language extensions to Siebel Analytics (Oracle BI) Server:
  • Support for per-measure predicates in the form of: Filter(⟨measure⟩ By ⟨predicate⟩)
  • Support for time-shifted computation of measures: Ago(⟨measure⟩, ⟨time step⟩, ⟨#steps⟩)
  These features shipped with Oracle BI Server release 10.1, and have a wide adoption.

• Senior Member of Technical Staff, Oracle Corporation (6/17/2002 - 2/15/2005). Researched, designed, and implemented following features in Oracle 10g SQL execution engine:
  • Right-outer, right-semi, and right-anti join algorithms.
  • Several improvements to hash join execution code that resulted in significant performance gain on TPC-D database performance benchmark.
  • Caching mechanism for deterministic PL/SQL functions.

• Senior Software Engineer, Desana Systems (8/21/2000 - 3/15/2002). Project lead for content processing of XML and HTTP data. Designed, implemented, and evaluated algorithms for fast XPath rule evaluation on streaming XML data. Developed a software module for fast identification and extraction of HTTP protocol fields.

• Research Assistant, CS Department, UW-Madison (6/95 - 8/00). Partial querying is common in decision support systems as a means of exploring data. Two typical partial queries are: Top N, in which users ask for a subset of ordered answers, and First N, in which users do not have any preference.
  To effectively evaluate Top N queries, I developed a probabilistic query optimization framework in which predicate selectivities (and cardinalities of intermediate results) are modeled as random variables. In addition to being useful for Top N queries, this framework can be applied to query optimization with other resources, such as main memory and network bandwidth.
  When processing queries for First N answers, I achieved significant speed improvements by better memory utilization. Database statistics are instrumental in choosing what tuples should be kept in memory.

• Member of Technical Staff / Summer Intern, Database Principles Research Department, Bell Laboratories, Lucent Technologies (5/99 - 8/99). Worked on Aqua, an approximate query answering system from Bell Labs. Co-developed a new form of database statistics called Quantized Samples, which has higher precision than traditional samples, given the same space.

• Teaching Assistant, Physics Department, University of Wisconsin-Madison (1/95 - 6/95). Taught college physics for undergraduate engineering students.

• Query Processor for DEVise
  DEVise is a visualization tool that uses SQL to select data to be displayed. I developed DEVise's query processor, which can do distributed query processing over heterogeneous data sources such as: local file systems, the Web, and ODBC databases.

• Astra Query Optimizer
  Developed a query optimizer based on the A* search algorithm (Astra). The optimizer is suitable for distributed query optimization because it can predict query costs at remote sites by importing their optimization rules. Astra is used in DEVise.

• SQL processor in Java
  Closely supervised and directed a team of four graduate students in successfully developing Java based query processor and execution engine.

1. Donko Donjerkovic, Yannis E. Ioannidis, Raghu Ramakrishnan. Dynamic Histograms: Capturing Evolving Data Sets, Proceedings of the 16th International Conference on Data Engineering, San Diego, California, USA, February 2000.
2. Donko Donjerkovic, Raghu Ramakrishnan. Probabilistic Optimization of Top N Queries, Proceedings of 25th International Conference on Very Large Databases, Edinburgh - Scotland, September 1999.
3. Raghu Ramakrishnan, Donko Donjerkovic, Arvind Ranganathan, Kevin S. Beyer, Muralidhar Krishnaprasad. SRQL: Sorted Relational Query Language, Proceedings of 10th International Conference on Scientific and Statistical Database Management, Capri, Italy, July, 1998.
4. Miron Livny, Raghu Ramakrishnan, Kevin S. Beyer, Guangshun Chen, Donko Donjerkovic, Shilpa Lawande, Jussi Myllymaki, R. Kent Wenger.DEVise: Integrated Querying and Visual Exploration of Large Datasets, Proceedings of ACM SIGMOD International Conference on Management of Data, Tucson, Arizona, USA, May 1997.

TECHNICAL REPORTS

1. Donko Donjerkovic, Swarup Acharya, Phillip Gibbons, Viswanath Poosala. Quantized Samples: Improving Accuracy by Blurring Values, Bell-Labs Technical Report, August 1999.
2. Donko Donjerkovic, Yannis Ioannidis, Raghu Ramakrishnan. Dynamic Histograms: Capturing Evolving Datasets, UW-Madison Technical Report 1396, March 1999.
3. Donko Donjerkovic, Raghu Ramakrishnan. Histogram Guided Partial Query Evaluation, UW-Madison Technical Report 1419, August 2000.

• Languages: C++ / C, SQL, MDX, XML / XPath, PHP, Java, Perl, Tcl / Tk
• APIs: ODBC, JDBC
• Protocols: HTTP, TCP/IP