mrigger
Joined 6 years ago
Karma
166
Submissions
20
Member since
Jun 7
Researcher at ETH Zurich, Switzerland. https://twitter.com/RiggerManuel
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Comment · 4 years ago
More information at https://modus-continens.com/.
Comment · 6 years ago
From the report at https://abertschi.ch/default_public/ethz/graalphp/download.p...: "Experimental results indicate that our runtime reaches competitive results with performance gains of up to 859% compared to PHP 7. These preliminary results suggest that a Truffle-hosted PHP implementation might be significantly faster than existing language implementations."
Comment · 6 years ago
For DBMS, the authors of the APOLLO system found the following [1]:
"Code coverage is a frequently used feedback mechanism in fuzzing engines [22, 27]. We found that this metric is not particularly useful for fuzzing DBMSs, since the core components of DBMS (e.g., query optimizer) already have high coverage (e.g., >95%) after running tens of queries."
[1] APOLLO: Automatic Detection and Diagnosis of Performance Regressions in Database Systems http://www.vldb.org/pvldb/vol13/p57-jung.pdf
Comment · 6 years ago
Yes, you are right, the results are not comparable between DBMS that we tested. For MySQL, the large number of existing bugs prevented us from going further, and also testing more advanced functionality (like FTS). For SQLite (and DuckDB), bugs were typically fixed within hours, which is why we could comprehensively test them. For SQLite, we also tested three extensions (besides FTS, also R*Tree and DBSTAT).
Comment · 6 years ago
I believe that the approaches that we designed could be implemented/extended to document-oriented DBMS. Since I don't have any experience with those DBMS, I have no intuition on whether the approaches would uncover any bugs.
Implementation-wise, supporting CouchDB and MongoDB in SQLancer would be feasible. SQLancer shares little infrastructure between the testing implementations for the individual DBMS, and thus imposes only few restrictions on them. We would definitely welcome implementations for any NoSQL DBMS in SQLancer!
Comment · 6 years ago
Thanks for your interest! I'd love to test H2, but we are currently lacking the resources to do so. We've received a number of similar requests in the last couple of days and weeks. For each DBMS that we test, we need to add some logic to randomly generate databases and queries, since the SQL dialects typically differ. I've opened an issue in SQLancer's issue tracker for now: https://github.com/sqlancer/sqlancer/issues/23