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Bishwaranjan Bhattacharjee

dblp:19/2910 · DBLP profile ↗
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27ranked-venue papers
6as first author
4since 2021 · last 2025
0009-0009-7097-4891ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Databases, data management, data science and information retrieval · 23 · 6 first-authorArtificial intelligence and machine learning · 2 · 2 since 2021Graphics, computer vision, multimedia, augmented reality and games · 2 · 2 since 2021Human-computer interaction and ubiquitous computing · 1 · 1 since 2021Applied, interdisciplinary, general and emerging computing · 1

Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.

Databases, data mining, and information retrieval
17 papers
Data mining · 26% Graph data management · 20% Indexing and storage engines · 18%
Artificial intelligence
3 papers
Transfer learning and domain adaptation · 57% Efficient and distributed learning · 22% Vision and language · 14%
Computer architecture, parallel and distributed computing, and storage systems
5 papers
Storage systems · 100%

Topics — the 30 heaviest of 41, each with the papers that count most for it

TopicWeightPapersLastEvidence papers
Machine learning › Transfer learning and domain adaptation
cross-lingual transfer
0.712023
Cross-Lingual Transfer of Large Language Model by Visually-Derived Supervision Toward Low-Resource Languages · ACM Multimedia 2023
Machine learning › Transfer learning and domain adaptation › language adaptation
low-resource language adaptation
0.712023
Cross-Lingual Transfer of Large Language Model by Visually-Derived Supervision Toward Low-Resource Languages · ACM Multimedia 2023
Data mining › pattern mining › graph pattern mining
frequent subgraph mining
0.622018
Incremental Frequent Subgraph Mining on Large Evolving Graphs · ICDE 2018
Incremental Frequent Subgraph Mining on Large Evolving Graphs · IEEE Trans. Knowl. Data Eng. 2017
Machine learning › Efficient and distributed learning › automated machine learning
neural architecture search
0.512021
NASTransfer: Analyzing Architecture Transferability in Large Scale Neural Architecture Search · AAAI 2021
Storage systems
flash and SSD
0.432013
Making Updates Disk-I/O Friendly Using SSDs · Proc. VLDB Endow. 2013
SSD Bufferpool Extensions for Database Systems · Proc. VLDB Endow. 2010
An Object Placement Advisor for DB2 Using Solid State Storage · Proc. VLDB Endow. 2009
Indexing and storage engines
index maintenance
0.422014
Reducing Database Locking Contention Through Multi-version Concurrency · Proc. VLDB Endow. 2014
Making Updates Disk-I/O Friendly Using SSDs · Proc. VLDB Endow. 2013
Data mining › structured data mining › graph mining › dynamic network analysis
dynamic graph mining
0.312018
Incremental Frequent Subgraph Mining on Large Evolving Graphs · ICDE 2018
Data mining
pattern mining
0.312018
Incremental Frequent Subgraph Mining on Large Evolving Graphs · ICDE 2018
Graph data management
dynamic graph
0.312017
Incremental Frequent Subgraph Mining on Large Evolving Graphs · IEEE Trans. Knowl. Data Eng. 2017
Transaction processing and concurrency control › concurrency control
multiversion concurrency control
0.322016
Reducing Database Locking Contention Through Multi-version Concurrency · Proc. VLDB Endow. 2014
Exploiting SSDs in operational multiversion databases · VLDB J. 2016
Transaction processing and concurrency control › versioning
multi-version databases
0.212016
Exploiting SSDs in operational multiversion databases · VLDB J. 2016
Storage systems › flash and SSD
solid-state drive
0.212016
Exploiting SSDs in operational multiversion databases · VLDB J. 2016
Indexing and storage engines
multiversion index
0.212014
Reducing Database Locking Contention Through Multi-version Concurrency · Proc. VLDB Endow. 2014
Transaction processing and concurrency control › isolation levels
snapshot isolation
0.212014
Reducing Database Locking Contention Through Multi-version Concurrency · Proc. VLDB Endow. 2014
Indexing and storage engines
buffer management
0.222010
SSD Bufferpool Extensions for Database Systems · Proc. VLDB Endow. 2010
Increasing Buffer-Locality for Multiple Relational Table Scans through Grouping and Throttling · ICDE 2007
Information retrieval › cross-language information retrieval
query translation
0.212013
Building an efficient RDF store over a relational database · SIGMOD Conference 2013
Graph data management › RDF data management
RDF query processing
0.212013
Building an efficient RDF store over a relational database · SIGMOD Conference 2013
Graph data management › RDF data management
relational storage of RDF
0.212013
Building an efficient RDF store over a relational database · SIGMOD Conference 2013
Computer vision › Image recognition and object detection
image classification
0.112021
NASTransfer: Analyzing Architecture Transferability in Large Scale Neural Architecture Search · AAAI 2021
Query processing and optimization
query rewriting
0.122008
Optimizing Hierarchical Access in OLAP Environment · ICDE 2008
Predicate Derivation and Monotonicity Detection in DB2 UDB · ICDE 2005
Computer vision › Vision and language › multimodal understanding
multimodal language analysis
0.112020
Visual Concept Naming: Discovering Well-Recognized Textual Expressions of Visual Concepts · WWW 2020
Indexing and storage engines
multidimensional clustering
0.122007
Efficient Bulk Deletes for Multi Dimensionally Clustered Tables in DB2 · VLDB 2007
Multi-Dimensional Clustering: A New Data Layout Scheme in DB2 · SIGMOD Conference 2003
Database system architecture and tuning › database design
physical database design
0.122009
An Object Placement Advisor for DB2 Using Solid State Storage · Proc. VLDB Endow. 2009
Automated design of multidimensional clustering tables for relational databases · VLDB 2004
Graph data management › graph pattern matching › subgraph matching
subgraph isomorphism
0.112018
Incremental Frequent Subgraph Mining on Large Evolving Graphs · ICDE 2018
Information retrieval › indexing
index compression
0.112009
Efficient Index Compression in DB2 LUW · Proc. VLDB Endow. 2009
Distributed and cloud data management › data placement
object placement
0.112009
An Object Placement Advisor for DB2 Using Solid State Storage · Proc. VLDB Endow. 2009
Query processing and optimization › OLAP
OLAP query optimization
0.112008
Optimizing Hierarchical Access in OLAP Environment · ICDE 2008
Query processing and optimization › query execution › scan processing
index scan
0.112007
Increasing Buffer-Locality for Multiple Index Based Scans through Intelligent Placement and Index Scan Speed Control · VLDB 2007
Transaction processing and concurrency control › transaction performance
transaction throughput
0.012013
Making Updates Disk-I/O Friendly Using SSDs · Proc. VLDB Endow. 2013
Indexing and storage engines › storage management
data layout
0.012003
Multi-Dimensional Clustering: A New Data Layout Scheme in DB2 · SIGMOD Conference 2003

Methods — techniques the papers use, named apart from their topics

image search · 0.9crowdsourcing · 0.9vokenization · 0.7visual supervision · 0.7subgraph isomorphism · 0.6fringe-based pruning · 0.6transfer learning · 0.5storage optimization · 0.5neural architecture search · 0.5incremental mining · 0.3embedding index · 0.3pessimistic concurrency control · 0.2optimistic concurrency control · 0.2kv-indirection structure · 0.2shredding of RDF into relational · 0.2query translation · 0.2indirection · 0.2batching · 0.2
YearPublicationVenuePosition
2025 A Simple-Yet-Efficient Instruction Augmentation Method for Zero-Shot Sentiment Classification
abstract
Instruction tuning significantly enhances the performance of large language models in tasks such as sentiment classification. Previous studies have leveraged labeled instances from sentiment benchmark datasets to instruction-tune LLMs, improving zero-shot sentiment classification performance. In this work, we propose a simple-yet-efficient instruction augmentation method which does not rely on any actual labeled sentiment instances. With just 240 pseudo instruction instances, the proposed method significantly improve the classification performance across several LLMs on 12 benchmark datasets, increasing scores by 30 points and outperforming LLMs that utilize more complex instruction tuning methods by 5.1 points. Surprisingly, the models tuned with 240 pseudo-instructions even outperform those tuned with actual domain-specific instruction instances. Despite method’s simplicity, our further analysis suggests that the probability shift toward the positive and negative classes and its generalization ability may be the primary driver of the improvement.
Masayasu Muraoka, Issei Yoshida, Bishwaranjan Bhattacharjee, Hiroshi Kanayama
COLING4
2024 DoubleDistillation: Enhancing LLMs for Informal Text Analysis using Multistage Knowledge Distillation from Speech and Text
abstract
Traditional large language models (LLMs) leverage extensive text corpora but lack access to acoustic and para-linguistic cues present in speech. There is a growing interest in enhancing text-based models with audio information. However, current models often require an aligned audio-text dataset which is frequently much smaller than typical language model training corpora. Moreover, these models often require both text and audio streams during inference/testing. In this study, we introduce a novel two-stage knowledge distillation (KD) approach that enables language models to (a) incorporate rich acoustic and paralinguistic information from speech, (b) utilize text corpora comparable in size to typical language model training data, and (c) support text-only analysis without requiring an audio stream during inference/testing. Specifically, we employ a pre-trained speech embedding teacher model (OpenAI Whisper) to train a Teacher Assistant (TA) model on an aligned audio-text dataset in the first stage. In the second stage, the TA’s knowledge is transferred to a student language model trained on a conventional text dataset. Thus, our two-stage KD method leverages both the acoustic and paralinguistic cues in the aligned audio-text data and the nuanced linguistic knowledge in a large text-only dataset. Based on our evaluation, this DoubleDistillation system consistently outperforms traditional LLMs in 15 informal text understanding tasks.
Fatema Hasan, James R. Foulds, Shimei Pan, Bishwaranjan Bhattacharjee
ICMI5
2023 Cross-Lingual Transfer of Large Language Model by Visually-Derived Supervision Toward Low-Resource Languages
abstract
Recent progress on vision and language research has shown that visual supervision improves the performance of large language models (LLMs) in various natural language processing (NLP) tasks. In particular, the Vokenization approach [65] initiated a new way of incorporating visual information into LLM training, demonstrating the potential of visual supervision for NLP tasks in a monolingual (i.e., English) setting. Given the effectiveness of visual information in human communication among people who speak different languages, we tackle an ambitious question in this paper; can we expect that visual supervision contributes to cross-lingual transfer learning from a high-resource language to low-resource languages in NLP tasks? To study this hypothesis, we build a cross-lingual Vokenization model and train a cross-lingual LLM on three languages, English, Urdu, and Swahili, in which the last two are considered low-resource languages. The experimental results demonstrate that our visually-supervised cross-lingual transfer learning method significantly improves the LLM performance in multiple cross-lingual NLP tasks such as XNLI, NER, and TyDiQA tasks for low-resource languages. We also qualitatively and quantitatively demonstrate that the benefit of our approach increases as the linguistic distance between low-and high-resource languages grows larger.
Masayasu Muraoka, Bishwaranjan Bhattacharjee, Michele Merler, Graeme Blackwood
ACM Multimedia2
2021 NASTransfer: Analyzing Architecture Transferability in Large Scale Neural Architecture Search
abstract
Neural Architecture Search (NAS) is an open and challenging problem in machine learning. While NAS offers great promise, the prohibitive computational demand of most of the existing NAS methods makes it difficult to directly search the architectures on large-scale tasks. The typical way of conducting large scale NAS is to search for an architectural building block on a small dataset (either using a proxy set from the large dataset or a completely different small scale dataset) and then transfer the block to a larger dataset. Despite a number of recent results that show the promise of transfer from proxy datasets, a comprehensive evaluation of different NAS methods studying the impact of different source datasets has not yet been addressed. In this work, we propose to analyze the architecture transferability of different NAS methods by performing a series of experiments on large scale benchmarks such as ImageNet1K and ImageNet22K. We find that: (i) The size and domain of the proxy set does not seem to influence architecture performance on the target dataset. On average, transfer performance of architectures searched using completely different small datasets (e.g., CIFAR10) perform similarly to the architectures searched directly on proxy target datasets. However, design of proxy sets has considerable impact on rankings of different NAS methods. (ii) While different NAS methods show similar performance on a source dataset (e.g., CIFAR10), they significantly differ on the transfer performance to a large dataset (e.g., ImageNet1K). (iii) Even on large datasets, random sampling baseline is very competitive, but the choice of the appropriate combination of proxy set and search strategy can provide significant improvement over it. We believe that our extensive empirical analysis will prove useful for future design of NAS algorithms.
Rameswar Panda, Michele Merler, Mayoore S. Jaiswal, Hui Wu 0009, Kandan Ramakrishnan, Ulrich Finkler, Chun-Fu Chen 0001, Minsik Cho, Rogério Feris, David S. Kung 0001, Bishwaranjan Bhattacharjee
AAAI11
2020 Visual Concept Naming: Discovering Well-Recognized Textual Expressions of Visual Concepts
abstract
We propose a task called Visual Concept Naming to associate visual concepts with the corresponding textual expressions, i.e., names of visual concepts found in real-world multimodal data. To tackle the task, we create a dataset consisting of 3.4 million tweets in total in three languages. We also propose a method for extracting candidate names of visual concepts and validating them by exploiting Web-based knowledge obtained through image search. To demonstrate the capability of our method, we conduct an experiment with the dataset we create and evaluate names obtained by our method through crowdsourcing, where we establish an evaluation method to verify the names. The experimental results indicate that the proposed method can identify a wide variety of names of visual concepts. The names we obtained also show interesting insights regarding languages and countries where the languages are used.1
Masayasu Muraoka, Tetsuya Nasukawa, Raymond H. Putra, Bishwaranjan Bhattacharjee
WWW4
2018 L-Store: A Real-time OLTP and OLAP System
Mohammad Sadoghi, Souvik Bhattacherjee, Bishwaranjan Bhattacharjee, Mustafa Canim
EDBT3
2018 Incremental Frequent Subgraph Mining on Large Evolving Graphs
abstract
Frequent subgraph mining is a core graph operation used in many domains. Most existing techniques target static graphs. However, modern applications utilize large evolving graphs. Mining these graphs using existing techniques is infeasible because of the high computational cost. We propose IncGM+, a fast incremental approach for frequent subgraph mining on large evolving graphs. We adapt the notion of "fringe" to the graph context, that is, the set of subgraphs on the border between frequent and infrequent subgraphs. IncGM+ maintains fringe subgraphs and exploits them to prune the search space. To boost efficiency, IncGM+ stores a number of selected embeddings to avoid redundant expensive subgraph isomorphism operations. Moreover, the proposed system supports batch updates. Our results confirm that IncGM+ outperforms existing methods, scales to larger graphs and consumes less memory.
Ehab Abdelhamid, Mustafa Canim, Mohammad Sadoghi, Bishwaranjan Bhattacharjee, Yuan-Chi Chang, Panos Kalnis
ICDE4
2017 Incremental Frequent Subgraph Mining on Large Evolving Graphs
abstract
Frequent subgraph mining is a core graph operation used in many domains, such as graph data management and knowledge exploration, bioinformatics, and security. Most existing techniques target static graphs. However, modern applications, such as social networks, utilize large evolving graphs. Mining these graphs using existing techniques is infeasible, due to the high computational cost. In this paper, we propose IncGM+, a fast incremental approach for continuous frequent subgraph mining on a single large evolving graph. We adapt the notion of “fringe” to the graph context, that is the set of subgraphs on the border between frequent and infrequent subgraphs. IncGM+ maintains fringe subgraphs and exploits them to prune the search space. To boost the efficiency, we propose an efficient index structure to maintain selected embeddings with minimal memory overhead. These embeddings are utilized to avoid redundant expensive subgraph isomorphism operations. Moreover, the proposed system supports batch updates. Using large real-world graphs, we experimentally verify that IncGM+ outperforms existing methods by up to three orders of magnitude, scales to much larger graphs and consumes less memory.
Ehab Abdelhamid, Mustafa Canim, Mohammad Sadoghi, Bishwaranjan Bhattacharjee, Yuan-Chi Chang, Panos Kalnis
IEEE Trans. Knowl. Data Eng.4
2016 Exploiting SSDs in operational multiversion databases
Mohammad Sadoghi, Kenneth A. Ross, Mustafa Canim, Bishwaranjan Bhattacharjee
VLDB J.4
2014 Reducing Database Locking Contention Through Multi-version Concurrency
abstract
In multi-version databases, updates and deletions of records by transactions require appending a new record to tables rather than performing in-place updates. This mechanism incurs non-negligible performance overhead in the presence of multiple indexes on a table, where changes need to be propagated to all indexes. Additionally, an uncommitted record update will block other active transactions from using the index to fetch the most recently committed values for the updated record. In general, in order to support snapshot isolation and/or multi-version concurrency, either each active transaction is forced to search a database temporary area (e.g., roll-back segments) to fetch old values of desired records, or each transaction is forced to scan the entire table to find the older versions of the record in a multi-version database (in the absence of specialized temporal indexes). In this work, we describe a novel kV-Indirection structure to enable efficient (parallelizable) optimistic and pessimistic multi-version concurrency control by utilizing the old versions of records (at most two versions of each record) to provide direct access to the recent changes of records without the need of temporal indexes. As a result, our technique results in higher degree of concurrency by reducing the clashes between readers and writers of data and avoiding extended lock delays. We have a working prototype of our concurrency model and kV-Indirection structure in a commercial database and conducted an extensive evaluation to demonstrate the benefits of our multi-version concurrency control, and we obtained orders of magnitude speed up over the single-version concurrency control.
Mohammad Sadoghi, Mustafa Canim, Bishwaranjan Bhattacharjee, Fabian Nagel, Kenneth A. Ross
Proc. VLDB Endow.3
2013 Building an efficient RDF store over a relational database
abstract
Efficient storage and querying of RDF data is of increasing importance, due to the increased popularity and widespread acceptance of RDF on the web and in the enterprise. In this paper, we describe a novel storage and query mechanism for RDF which works on top of existing relational representations. Reliance on relational representations of RDF means that one can take advantage of 35+ years of research on efficient storage and querying, industrial-strength transaction support, locking, security, etc. However, there are significant challenges in storing RDF in relational, which include data sparsity and schema variability. We describe novel mechanisms to shred RDF into relational, and novel query translation techniques to maximize the advantages of this shredded representation. We show that these mechanisms result in consistently good performance across multiple RDF benchmarks, even when compared with current state-of-the-art stores. This work provides the basis for RDF support in DB2 v.10.1.
Mihaela A. Bornea, Julian Dolby, Anastasios Kementsietsidis, Kavitha Srinivas, Patrick Dantressangle, Octavian Udrea, Bishwaranjan Bhattacharjee
SIGMOD Conference7
2013 Making Updates Disk-I/O Friendly Using SSDs
abstract
Multiversion databases store both current and historical data. Rows are typically annotated with timestamps representing the period when the row is/was valid. We develop novel techniques for reducing index maintenance in multiversion databases, so that indexes can be used effectively for analytical queries over current data without being a heavy burden on transaction throughput. To achieve this end, we re-design persistent index data structures in the storage hierarchy to employ an extra level of indirection. The indirection level is stored on solid state disks that can support very fast random I/Os, so that traversing the extra level of indirection incurs a relatively small overhead. The extra level of indirection dramatically reduces the number of magnetic disk I/Os that are needed for index updates, and localizes maintenance to indexes on updated attributes. Further, we batch insertions within the indirection layer in order to reduce physical disk I/Os for indexing new records. By reducing the index maintenance overhead on transactions, we enable operational data stores to create more indexes to support queries. We have developed a prototype of our indirection proposal by extending the widely used Generalized Search Tree (GiST) open-source project, which is also employed in PostgreSQL. Our working implementation demonstrates that we can significantly reduce index maintenance and/or query processing cost, by a factor of 3. For insertions of new records, our novel batching technique can save up to 90% of the insertion time.
Mohammad Sadoghi, Kenneth A. Ross, Mustafa Canim, Bishwaranjan Bhattacharjee
Proc. VLDB Endow.4
2011 Enhancing recovery using an SSD buffer pool extension
abstract
Recent advances in solid state technology have led to the introduction of solid state drives (SSDs). Today's SSDs store data persistently using NAND flash memory and support good random IO performance. Current work in exploiting flash in database systems has primarily focused on using its random IO capability for second level bufferpools below main memory. There has not been much emphasis on exploiting its persistence.
Bishwaranjan Bhattacharjee, Kenneth A. Ross, Christian A. Lang, George A. Mihaila, Mohammad Banikazemi
DaMoN1
2011 Column-oriented query processing for row stores
abstract
Column-oriented DBMSs have gained increasing interest due to their superior performance for analytical workloads. Prior efforts tried to determine the possibility of simulating the query processing techniques of column-oriented systems in row-oriented databases, in a hope to improve their performance, especially for OLAP and data warehousing applications. In this paper, we show that column-oriented query processing can significantly improve the performance of row-oriented DBMSs. We introduce new operators that take into account the unique characteristics of data obtained from indexes, and exploit new technologies such as flash SSDs and multi-core processors to boost the performance. We demonstrate our approach with an experimental study using a prototype built on a commercial row-oriented DBMS.
Amr El-Helw, Kenneth A. Ross, Bishwaranjan Bhattacharjee, Christian A. Lang, George A. Mihaila
DOLAP3
2010 SSD Bufferpool Extensions for Database Systems
abstract
High-end solid state disks (SSDs) provide much faster access to data compared to conventional hard disk drives. We present a technique for using solid-state storage as a caching layer between RAM and hard disks in database management systems. By caching data that is accessed frequently, disk I/O is reduced. For random I/O, the potential performance gains are particularly significant. Our system continuously monitors the disk access patterns to identify hot regions of the disk. Temperature statistics are maintained at the granularity of an extent, i.e., 32 pages, and are kept current through an aging mechanism. Unlike prior caching methods, once the SSD is populated with pages from warm regions cold pages are not admitted into the cache, leading to low levels of cache pollution. Simulations based on DB2 I/O traces, and a prototype implementation within DB2 both show substantial performance improvements.
Mustafa Canim, George A. Mihaila, Bishwaranjan Bhattacharjee, Kenneth A. Ross, Christian A. Lang
Proc. VLDB Endow.3
2009 Efficient Index Compression in DB2 LUW
abstract
In database systems, the cost of data storage and retrieval are important components of the total cost and response time of the system. A popular mechanism to reduce the storage footprint is by compressing the data residing in tables and indexes. Compressing indexes efficiently, while maintaining response time requirements, is known to be challenging. This is especially true when designing for a workload spectrum covering both data warehousing and transaction processing environments. DB2 Linux, UNIX, Windows (LUW) recently introduced index compression for use in both environments. This uses techniques that are able to compress index data efficiently while incurring virtually no performance penalty for query processing. On the contrary, for certain operations, the performance is actually better. In this paper, we detail the design of index compression in DB2 LUW and discuss the challenges that were encountered in meeting the design goals. We also demonstrate its effectiveness by showing performance results on typical customer scenarios.
Bishwaranjan Bhattacharjee, Lipyeow Lim, Timothy Malkemus, George A. Mihaila, Kenneth A. Ross, Sherman Lau, Cathy McCarthur, Zoltan Toth, Reza Sherkat
Proc. VLDB Endow.1
2009 An Object Placement Advisor for DB2 Using Solid State Storage
abstract
Solid state disks (SSDs) provide much faster random access to data compared to conventional hard disk drives. Therefore, the response time of a database engine could be improved by moving the objects that are frequently accessed in a random fashion to the SSD. Considering the price and limited storage capacity of solid state disks, the database administrator needs to determine which objects (tables, indexes, materialized views, etc.), if placed on the SSD, would most improve the performance of the system. In this paper we propose a tool called "Object Placement Advisor" for making a wise decision for the object placement problem. By collecting profile inputs from workload runs, the advisor utility provides a list of objects to be placed on the SSD by applying heuristics like the greedy knapsack technique or dynamic programming. To show that the proposed approach is effective in conventional database management systems, we have conducted experiments on IBM DB2 with queries and schemas based on the TPC-H and TPC-C benchmarks. The results indicate that using a relatively small amount of SSD storage, the response time of the system can be reduced significantly by considering the recommendation of the advisor.
Mustafa Canim, Bishwaranjan Bhattacharjee, George A. Mihaila, Christian A. Lang, Kenneth A. Ross
Proc. VLDB Endow.2
2008 Optimizing Hierarchical Access in OLAP Environment
abstract
In online analytic processing (OLAP) deployments, different users, lines of businesses and business units often create adhoc aggregation hierarchies tailor-made for specific reporting or analytical applications. As a result, a large number of these application specific hierarchies accumulate over time. System administrators typically are not able to optimize all these hierarchical accesses by hand due to the large number of hierarchies. However, many optimization opportunities exist due to the significant amount of overlap between some hierarhies. In this paper, we sketch a novel method for optimizing OLAP aggregation queries using precomputed aggregates on other overlapping hierarchies. Our method detects common sub-structures among hierarchies and provides a rewriting algorithm to exploit any precomputations on these shared sub-structures.
Lipyeow Lim, Bishwaranjan Bhattacharjee
ICDE2
2007 Impliance: A Next Generation Information Management Appliance
Bishwaranjan Bhattacharjee, Joseph S. Glider, Richard A. Golding, Guy M. Lohman, Volker Markl, Hamid Pirahesh, Jun Rao, Robert M. Rees, Garret Swart
CIDR1
2007 Increasing Buffer-Locality for Multiple Relational Table Scans through Grouping and Throttling
abstract
Decision support (DSS) workloads generally contain multiple large concurrent scan operations. These are often executed as relational table scans which can take up a lot of I/O bandwidth. This is especially true for ad-hoc queries where the workload is not known in advance. Common database management systems have only limited ability to reuse memory buffer content across multiple running queries due to their treatment of queries in isolation. Previous attempts to coordinate scans for better buffer reuse were less than satisfactory due to drifting between scans and the required radical DBMS architecture changes. In this paper, we describe a new mechanism to keep similar table scans closer together during scanning. This is achieved via dynamic grouping and regrouping of scans based on their runtime behavior and via adaptive throttling of scan speeds based on scan group characteristics. The required memory footprint is very small and the effort required to extend existing database management systems is minimal, as shown in our DB2 UDB prototype. Our experiments show significant gains in end-to-end response times as well as average response times for TPC-H workloads.
Christian A. Lang, Bishwaranjan Bhattacharjee, Timothy Malkemus, Sriram Padmanabhan, Kwai Wong
ICDE2
2007 Efficient Bulk Deletes for Multi Dimensionally Clustered Tables in DB2
Bishwaranjan Bhattacharjee, Timothy Malkemus, Sherman Lau, Sean Mckeough, Jo-Anne Kirton, Robin Von Boeschoten, John Kennedy
VLDB1
2007 Increasing Buffer-Locality for Multiple Index Based Scans through Intelligent Placement and Index Scan Speed Control
Christian A. Lang, Bishwaranjan Bhattacharjee, Timothy Malkemus, Kwai Wong
VLDB2
2006 Using secure coprocessors for privacy preserving collaborative data mining and analysis
abstract
Secure coprocessors have traditionally been used as a keystone of a security subsystem, eliminating the need to protect the rest of the subsystem with physical security measures. With technological advances and hardware miniaturization they have become increasingly powerful. This opens up the possibility of using them for non traditional use. This paper describes a solution for privacy preserving data sharing and mining using cryptographically secure but resource limited coprocessors. It uses memory light data mining methodologies along with a light weight database engine with federation capability, running on a coprocessor. The data to be shared resides with the enterprises that want to collaborate. This system will allow multiple enterprises, which are generally not allowed to share data, to do so solely for the purpose of detecting particular types of anomalies and for generating alerts. We also present results from experiments which demonstrate the value of such collaborations.
Bishwaranjan Bhattacharjee, Naoki Abe, Kenneth A. Goldman, Bianca Zadrozny, Vamsavardhana R. Chillakuru, Marysabel del Carpio, Chidanand Apté
DaMoN1
2005 Predicate Derivation and Monotonicity Detection in DB2 UDB
abstract
DB2 universal database allows database schema designers to specify generated columns. These generated columns are useful for maintaining rollup hierarchy variables in warehouses (e.g., date, month, quarter). In order for the generated columns to be useful for query processing, queries must automatically make use of such columns when applicable. In particular, query predicates on the original columns should be rewritten to make use of the generated columns. In this paper, we describe two main aspects of this predicate rewriting technique that allows usage of the generated columns for a variety of query predicate types. The first aspect, monotonicity detection, allows for rewrites in the case of range predicates. The second aspect, predicate derivation, is the technique for using generating expressions for query processing. We show the value of this technique for providing significant performance improvement when combined with indexing or multidimensional clustering in DB2.
Timothy Malkemus, Sriram Padmanabhan, Bishwaranjan Bhattacharjee, Leslie Cranston
ICDE3
2004 Automated design of multidimensional clustering tables for relational databases
Sam Lightstone, Bishwaranjan Bhattacharjee
VLDB2
2003 Multi-Dimensional Clustering: A New Data Layout Scheme in DB2
abstract
We describe the design and implementation of a new data layout scheme, called multi-dimensional clustering, in DB2 Universal Database Version 8. Many applications, e.g., OLAP and data warehousing, process a table or tables in a database using a multi-dimensional access paradigm. Currently, most database systems can only support organization of a table using a primary clustering index. Secondary indexes are created to access the tables when the primary key index is not applicable. Unfortunately, secondary indexes perform many random I/O accesses against the table for a simple operation such as a range query. Our work in multi-dimensional clustering addresses this important deficiency in database systems. Multi-Dimensional Clustering is based on the definition of one or more orthogonal clustering attributes (or expressions) of a table. The table is organized physically by associating records with similar values for the dimension attributes in a cluster. We describe novel techniques for maintaining this physical layout efficiently and methods of processing database operations that provide significant performance improvements. We show results from experiments using a star-schema database to validate our claims of performance with minimal overhead.
Sriram Padmanabhan, Bishwaranjan Bhattacharjee, Timothy Malkemus, Leslie Cranston, Matthew Huras
SIGMOD Conference2
2003 Efficient Query Processing for Multi-Dimensionally Clustered Tables in DB2
Bishwaranjan Bhattacharjee, Sriram Padmanabhan, Timothy Malkemus, Tony Lai, Leslie Cranston, Matthew Huras
VLDB1