Date: 2016-11-09 11:16:43 +0100
From: Dean De Leo <>
To: SQL devs <>
Version: -- development
CC: @njnes

Last updated: 2016-12-21 13:08:12 +0100

Comment 24666

Date: 2016-11-09 11:16:43 +0100
From: Dean De Leo <>

User-Agent: Mozilla/5.0 (X11; Fedora; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.71 Safari/537.36
Build Identifier:

The attached query causes an assertion to be fired in the query rewriting stage.

On Linux, tip of the default branch, debug build, empty tables.

Reproducible: Always

Steps to Reproduce:

1. Load the attached schema.
2. Issue the attached query
3. An assertion is fired by the server

Actual Results:

See the attached backtrace

Expected Results:

Server failures are bad. Assuming they should never occur.

Comment 24667

Date: 2016-11-09 11:17:22 +0100
From: Dean De Leo <>

Created attachment 500
Database schema

Attached file: schema.sql (application/sql, 7731 bytes)
Description: Database schema

Comment 24668

Date: 2016-11-09 11:17:38 +0100
From: Dean De Leo <>

Created attachment 501
Repro query (query4.sql)

Attached file: query4.sql (application/sql, 897 bytes)
Description: Repro query (query4.sql)

Comment 24669

Date: 2016-11-09 11:17:57 +0100
From: Dean De Leo <>

Created attachment 502
Backtrace

Attached file: backtrace4.txt (text/plain, 3553 bytes)
Description: Backtrace

Comment 24673

Date: 2016-11-09 23:07:16 +0100
From: MonetDB Mercurial Repository <>

Changeset bfc05edc1fa1 made by Niels Nes niels@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=bfc05edc1fa1

Changeset description:

fixes for bugs 6114, 6115, 6116 and 6117

improved dead code elimination for cases with references to sub queries (ie its a dag)
push simple select like expressions downs

split_project test is added here but only crashes in the dec2016/default.

Comment 24677

Date: 2016-11-10 08:07:22 +0100
From: @njnes

we cannot split expressions in set operators. Also improved the handling of the split project optimizer