apache/impala
Nov 2025 – Dec 2025
2 Months active
Languages Used
JavaC++
Technical Skills
Javaback end developmentdatabase managementC++ developmentmemory managementperformance optimization
Nandor Kollar
PROFILE
Nandor Kollar
Nandor Kollar contributed to the apache/impala repository by developing a table conversion format versioning feature and addressing a memory management issue. He implemented the ability to specify format versions in ALTER TABLE CONVERT TO statements, adding strict validation to prevent unsupported configurations and improve conversion robustness. In a separate effort, he resolved a memory leak in iceberg data handling by refactoring completed-queries vector allocation from heap to stack within C++, reducing heap fragmentation and enhancing stability under concurrent workloads. His work demonstrated proficiency in C++ and Java, with a focus on back end development, database management, and performance optimization.
Overall Statistics
Feature vs Bugs
50%Features
Repository Contributions
2Total
Bugs
1
Commits
2
Features
1
Lines of code
96
Activity Months2
Your Network
46 peopleShared Repositories
46
Work History
December 2025
1 Commits
Dec 1, 2025December 2025: Stable, memory-efficient delivery in Apache Impala. Focused on memory management improvements for iceberg data handling, delivering a critical bug fix that reduces heap pressure and enhances reliability under long-running workloads.
1 Commits
Dec 1, 2025December 2025: Stable, memory-efficient delivery in Apache Impala. Focused on memory management improvements for iceberg data handling, delivering a critical bug fix that reduces heap pressure and enhances reliability under long-running workloads.
December 2025
November 2025
1 Commits • 1 Features
Nov 1, 2025November 2025 monthly summary for apache/impala focusing on the Table Conversion Format Versioning feature. The goal this month was to improve robustness and configurability of table conversions, with a clear property for format version and safeguards against invalid configurations.
November 2025
1 Commits • 1 Features
Nov 1, 2025November 2025 monthly summary for apache/impala focusing on the Table Conversion Format Versioning feature. The goal this month was to improve robustness and configurability of table conversions, with a clear property for format version and safeguards against invalid configurations.
Activity
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Quality Metrics
Correctness100.0%
Maintainability90.0%
Architecture90.0%
Performance90.0%
AI Usage30.0%
Skills & Technologies
Programming Languages
C++Java
Technical Skills
C++ developmentJavaback end developmentdatabase managementmemory managementperformance optimization
Repositories Contributed To
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