Publications by Ioannis Alagiannis

Adaptive partitioning and indexing for in situ query processing

Anastasia Ailamaki, Manoussos Gavriil Athanassoulis, Ioannis Alagiannis, Matthaios Alexandros Olma, Manolis Karpathiotakis

The constant flux of data and queries alike has been pushing the boundaries of data analysis systems. The increasing size of raw data files has made data loading an expensive operation that delays the data-to-insight time. To alleviate the loading cost, in ...

SPRINGER2020

Slalom: Coasting Through Raw Data via Adaptive Partitioning and Indexing

Anastasia Ailamaki, Manoussos Gavriil Athanassoulis, Ioannis Alagiannis, Matthaios Alexandros Olma, Manolis Karpathiotakis

The constant flux of data and queries alike has been pushing the boundaries of data analysis systems. The increasing size of raw data files has made data loading an expensive operation that delays the data-to-insight time. Hence, recent in-situ query proce ...

VLDB Endowment2017

Fast Queries Over Heterogeneous Data Through Engine Customization

Anastasia Ailamaki, Ioannis Alagiannis, Manolis Karpathiotakis

Industry and academia are continuously becoming more data-driven and data-intensive, relying on the analysis of a wide variety of heterogeneous datasets to gain insights. The different data models and formats pose a significant challenge on performing anal ...

Assoc Computing Machinery2016

DBMS Data Loading: An Analysis on Modern Hardware

Anastasia Ailamaki, Ioannis Alagiannis, Manolis Karpathiotakis, Adam Dziedzic, Raja Appuswamy

2016

Adaptive Query Processing on Raw Data Files

Ioannis Alagiannis

Nowadays, business and scientific applications accumulate data at an increasing pace. This growth of information has already started to outgrow the capabilities of database management systems (DBMS). In a typical DBMS usage scenario, the user should define ...

EPFL2015

NoDB: Efficient Query Execution on Raw Data Files

Anastasia Ailamaki, Ioannis Alagiannis, Renata Borovica-Gajic, Miguel Sérgio De Oliveira Branco

As data collections become larger and larger, users are faced with increasing bottlenecks in their data analysis. More data means more time to prepare and to load the data into the database before executing the desired queries. Many applications already av ...

Assoc Computing Machinery2015

Just-In-Time Data Virtualization: Lightweight Data Management with ViDa

Anastasia Ailamaki, Ioannis Alagiannis, Thomas Heinis, Miguel Sérgio De Oliveira Branco, Manolis Karpathiotakis

As the size of data and its heterogeneity increase, traditional database system architecture becomes an obstacle to data analysis. Integrating and ingesting (loading) data into databases is quickly becoming a bottleneck in face of massive data as well as i ...

2015

Adaptive Query Processing on RAW Data

Anastasia Ailamaki, Ioannis Alagiannis, Miguel Sérgio De Oliveira Branco, Manolis Karpathiotakis

Database systems deliver impressive performance for large classes of workloads as the result of decades of research into optimizing database engines. High performance, however, is achieved at the cost of versatility. In particular, database systems only op ...

2014

Query management system and engine allowing for efficient query execution on raw details

Anastasia Ailamaki, Ioannis Alagiannis, Renata Borovica-Gajic, Miguel Sérgio De Oliveira Branco

A database system maintains a feature set of a modern database system while operating directly on raw data files. Systems may use an adaptive indexing mechanism that maintains positional information to provide efficient access to raw data files, a flexible ...

2014

H2O: A Hands-free Adaptive Store

Anastasia Ailamaki, Ioannis Alagiannis

Modern state-of-the-art database systems are designed around a single data storage layout. This is a fixed decision that drives the whole architectural design of a database system, i.e., row-stores, column-stores. However, none of those choices is a univer ...

2014

DiNoDB: Efficient Large-Scale Raw Data Analytics

Marko Vukolic, Anastasia Ailamaki, Ioannis Alagiannis, Erietta Liarou, Yongchao Tian

Modern big data workflows, found in e.g., machine learning use cases, often involve iterations of cycles of batch analytics and interactive analytics on temporary data. Whereas batch analytics solutions for large volumes of raw data are well established (e ...

2014

Scaling up analytical queries with column-stores

Anastasia Ailamaki, Manoussos Gavriil Athanassoulis, Ioannis Alagiannis

As data analytics is used by an increasing number of applications, data analytics engines are required to execute workloads with increased concurrency, i.e., an increasing number of clients submitting queries. Data management systems designed for data anal ...

2013

NoDB: Efficient Query Execution on Raw Data Files

Anastasia Ailamaki, Ioannis Alagiannis, Renata Borovica-Gajic, Miguel Sérgio De Oliveira Branco

As data collections become larger and larger, data loading evolves to a major bottleneck. Many applications already avoid using database systems, e.g., scientific data analysis and social networks, due to the complexity and the increased data-to-query time ...

2012

NoDB in Action: Adaptive Query Processing on Raw Data

Anastasia Ailamaki, Ioannis Alagiannis, Renata Borovica-Gajic, Miguel Sérgio De Oliveira Branco

As data collections become larger and larger, users are faced with increasing bottlenecks in their data analysis. More data means more time to prepare the data, to load the data into the database and to execute the desired queries. Many applications alread ...

VLDB Endowment2012

Automated Physical Designers: What You See is (Not) What You Get

Anastasia Ailamaki, Ioannis Alagiannis, Renata Borovica-Gajic

The explosion of available data in the last few years has increased the importance of physical database design, since the selection of proper physical structures (e.g. indices, partitions and materialized views) may improve query execution performance by s ...

ACM2012

Challenges and Opportunities in Self-Managing Scientific Databases

Anastasia Ailamaki, Farhan Tauheed, Ioannis Alagiannis, Thomas Heinis, Renata Borovica-Gajic, Miguel Sérgio De Oliveira Branco

Advances in observation instruments and abundance of computational power for simulations encourage scientists to gather and produce unprecedented amounts of increasingly complex data. Organizing data automatically to enable efficient and unobstructed acces ...

2011