# FAQ: Questions Asked Frequently

@article{AboKhamis2016FAQQA, title={FAQ: Questions Asked Frequently}, author={Mahmoud Abo Khamis and Hung Quoc Ngo and Atri Rudra}, journal={Proceedings of the 35th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems}, year={2016} }

We define and study the Functional Aggregate Query (FAQ) problem, which encompasses many frequently asked questions in constraint satisfaction, databases, matrix operations, probabilistic graphical models and logic. This is our main conceptual contribution. We then present a simple algorithm called "InsideOut" to solve this general problem. InsideOut is a variation of the traditional dynamic programming approach for constraint programming based on variable elimination. Our variation adds a…

## 134 Citations

Juggling Functions Inside a Database

- Computer ScienceSGMD
- 2017

The framework tightly connects new ideas in database theory with a vast number of application areas in a coherent manner, showing potentially that a good database engine can be a general purpose constraint solver, relational data store, graphical model inference engine, and matrix/tensor computation processor all at once.

Functional Aggregate Queries with Additive Inequalities

- Computer ScienceACM Trans. Database Syst.
- 2020

This work defines relaxed tree decompositions and relaxed submodular and fractional hypertree width parameters and shows that an extension of the InsideOut algorithm using Chazelle’s geometric data structure for solving the semigroup range search problem can answer Boolean FAQ-AI in time given by these new width parameters.

On Functional Aggregate Queries with Additive Inequalities

- Computer SciencePODS
- 2019

It is shown that an extension of the InsideOut algorithm using Chazelle's geometric data structure for solving the semigroup range search problem can answer Boolean FAQ-AI in time given by these new width parameters.

Ranked Enumeration of Join Queries with Projections

- Computer Science
- 2022

This paper begins the study of the problem of enumerating results in ranked order for queries with projections, and shows that for any acyclic query, it is possible to obtain a near-linear delay algorithm after only a linear time preprocessing step for two important ranking functions: sum and lexicographic ordering.

Attacking Diophantus: Solving a Special Case of Bag Containment

- Computer SciencePODS
- 2019

Conjunctive-query containment is the problem of deciding whether the answers of a given conjunctive query on an arbitrary database instance are always contained in the answers of a second query on…

General dynamic Yannakakis: conjunctive queries with theta joins under updates

- Computer ScienceThe VLDB Journal
- 2019

First, full formal proof of GDyn ’s correctness and complexity is given and a novel algorithm for computing GDyn query plans is presented, which performs consistently better than the competitor systems with multiple orders of magnitude improvements in both time and memory consumption.

Any-k Algorithms for Enumerating Ranked Answers to Conjunctive Queries

- Computer Science, MathematicsArXiv
- 2022

“Any-k” algorithms are developed which, without knowing the number k of desired answers, push the ranking into joins and avoid materializing the join output earlier than necessary, to design a novel algorithm that asymptotically dominates all previously known alternatives.

Optimal Joins using Compact Data Structures

- Computer ScienceICDT
- 2020

It is shown that optimal algorithms can be obtained directly from a representation that regards the relations as point sets in variable-dimensional grids, without the need of extra storage, and developed a compositional algorithm to process full join queries under this representation.

AJAR: Aggregations and Joins over Annotated Relations

- Computer SciencePODS
- 2016

We study a class of aggregate-join queries with multiple aggregation operators evaluated over annotated relations. We show that straightforward extensions of standard multiway join algorithms and…

The Complexity of Aggregates over Extractions by Regular Expressions

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This work formally defines aggregate functions over regular document spanners and analyzes the computational complexity of exact and approximative computation of the aggregates.

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