Searcharxiv⌕ Search

arXiv · 2610.25131

Data.Readme: Documenting Table Relationships for Diverse Data Tasks

Abstract

Large language models (LLMs) can perform diverse data tasks when given a small set of relevant tables. However, for complex tasks requiring multiple tables over large data lakes, identifying relevant tables for the task becomes a prerequisite, but remains challenging. This is because there are often many tables in a data lake with similar table and schema names, and limited additional semantic context, thereby forcing agents to spend substantial time exploring tables at online query time, greatly affecting models' ability to perform tasks accurately, while increasing cost/latency substantially. We present Data.Readme, a novel table documentation approach that uses lightweight offline processing to infer and index rich \emph{table-to-table relationships}, including confusable, joinable, and union-able tables. We further develop a suite of agentic tools for LLMs to work with the index, to help agents retrieve relevant tables and perform tasks much more efficiently and effectively. Finally, we study how to optimize our index construction with a budget constraint. On data lakes containing up to 12K tables, Data.Readme improves task accuracy by as much as 40 percentage points across a range of data discovery, data analysis, and data science tasks, outperforming diverse baselines, including powerful coding agents with unlimited time and monetary budgets. We also show that equipping existing methods (such as coding agents) with Data.Readme can not only lead to consistent quality gains, but also significantly reduce their latency by up to 6x, demonstrating the potential of Data.Readme.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Jiaming Liang, Yeye He, Haoyu Dong, Zachary Ives, Surajit Chaudhuri. 2026-10-18. Data.Readme: Documenting Table Relationships for Diverse Data Tasks. https://arxiv.org/abs/2610.25131

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

A General LLM Framework for Query Refinement

Numerous studies have explored the SQL query refinement problem, where the objective is to minimally modify an input query so that its output satisfies a specified set of constraints. However, these works typically target restricted classes of queries or constraints. We present OmniTune, a general framework for refining arbitrary SQL queries using LLM-based optimization by prompting (OPRO). OmniTune employs a two-step OPRO scheme that explores promising refinement subspaces and samples candidates within them, supported by concise history and skyline summaries for effective feedback. Experiments on a comprehensive benchmark demonstrate that OmniTune handles both previously studied refinement tasks and more complex scenarios beyond the scope of existing solutions.

cs.DB↗

KatoANN: Enabling Near-Exact Vector Search at the Speed of Lossy Scans with CPU Matrix Engines

Distance scans in partition-family approximate nearest-neighbor (ANN) search are typically limited by memory bandwidth. Existing systems therefore improve throughput by reading fewer bytes per candidate, often at the cost of recall. We present KatoANN, a CPU ANN search system that removes this tradeoff by batching distance scans on Intel AMX, a CPU matrix engine. Batching allows multiple queries to reuse each fetched vector code, shifting the scan from memory-bound to compute-bound and enabling near-exact distances at the speed of a lossy scan. KatoANN stores each vector once as a 16-bit SQ16 code split into high- and low-byte planes. Its adaptive rank-then-refine scan first ranks all candidates using only the high byte, then refines a small survivor set using the full-byte code. Both stages use the same representation, avoiding a second copy of the raw vectors. Experiments across diverse high-dimensional workloads show that KatoANN is the fastest partition-family ANN search system in our evaluation throughout the high-recall range.

cs.DB↗

Local Inference of LLMs on Long Contexts: A Data Systems Perspective

Large language models can solve complex problems across a variety of subjects, such as mathematics and coding. For such complex analytical tasks, models with a long context perform better. Serving models with long context is currently mostly done on powerful systems with multiple GPUs, which are too expensive for most users. An alternative is local inference, or serving a model on a user's own machine, which removes per-token costs and rate limits, besides keeping sensitive data private and giving users full control over the models they run. The common understanding, however, is that local LLMs need compression (e.g., quantization) to run on a single GPU. In this paper, we set out to study the limitations that prevent serving long-context models for single users, besides the capacity issue. Rather than characterizing a single model on one GPU, we analyze how different models behave across several GPU generations. This lets us uncover not just individual bottlenecks but broader trends in where inefficiencies arise. Our analysis confirms that, as expected, self-attention dominates the runtime for long-context inference. More unexpectedly, our evaluation reveals that the current structure of self-attention leaves key GPU resources significantly underutilized, and the newest GPU is often the least well served. Many of these findings are fundamentally data management problems, from paging the KV cache to improving cache utilization and synchronization in the GPU, which is why we bring this study to the Data Systems community. To engage this community, we present our findings as a series of experimental observations and formulate recommendations for future work.

cs.DB↗