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We present a novel symbolic reasoning engine for SQL which can efficiently generate an inputIfornqueriesP1, ⋯,Pn, such that their outputs onIsatisfy a given property (expressed in SMT). This is useful in different contexts, such as disproving equivalence of two SQL queries and disambiguating a set of queries. Our first idea is to reason about an under-approximation of eachPi— that is, a subset ofPi’s input-output behaviors. While it makes our approach both semantics-aware and lightweight, this idea alone is incomplete (as a fixed under-approximation might miss some behaviors of interest). Therefore, our second idea is to perform search over an expressive family of under-approximations (which collectively cover all program behaviors of interest), thereby making our approach complete. We have implemented these ideas in a tool, Polygon, and evaluated it on over 30,000 benchmarks across two tasks (namely, SQL equivalence refutation and query disambiguation). Our evaluation results show that Polygon significantly outperforms all prior techniques.
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This content will become publicly available on July 1, 2026
Cultural transmission of animal tool use driven by trade-offs: insights from sponge-using dolphins
Although tool use offers obvious benefits to the user, the role of costs in the spread of tool use has received scant attention. Sponge tool use is a foraging technique restricted to a small subpopulation of bottlenose dolphins (Tursiops aduncus) in Shark Bay, Australia, that carry basket sponges on their beaks to probe the seafloor and flush out camouflaged fish, widening the search area and protecting the beak from abrasion. While most instances of animal tool use extend the phenotype, we hypothesized that sponges interfere with echolocation, particularly reception of echoes along the lower jaw. To evaluate how echolocation signals change while travelling through sponge tissue, we simulated echolocation using finite-element analysis based on digital models of sponge species (Echinodictyum mesenterinumandIrciniaspp.). We find that acoustic properties of the echolocation signal are changed in the presence ofIrciniaspp. and, to a lesser extent,E. mesenterinum. Given distortions vary with each sponge, dolphins must adaptively and flexibly compensate during neural signal processing. This explains why sponging takes so long to learn, is strictly vertically transmitted and does not spread to others despite close association with tool users. Taken together, these findings provide a compelling look at the underlying intrinsic and extrinsic forces shaping tool use in wild populations.
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- PAR ID:
- 10630158
- Publisher / Repository:
- Royal Society Publishing
- Date Published:
- Journal Name:
- Royal Society Open Science
- Volume:
- 12
- Issue:
- 7
- ISSN:
- 2054-5703
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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