case evaluted to early

[monetdb-team]

Date: 2012-11-16 12:11:58 +0100
From: @bartscheers
To: SQL devs <>
Version: 11.13.3 (Oct2012)
CC: @njnes

Last updated: 2013-01-22 09:29:11 +0100

Comment 17946

Date: 2012-11-16 12:11:58 +0100
From: @bartscheers

User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:16.0) Gecko/20100101 Firefox/16.0
Build Identifier:

sql> SELECT CASE WHEN TRUE THEN -10. ELSE 0/0 END;
division by zero.
but
sql>
sql>SELECT CASE WHEN TRUE THEN -10 ELSE 0/0 END;
+---------------------+
| isnull_single_value |
+=====================+
| -10 |
+---------------------+
1 tuple (1.992ms)

Reproducible: Always

Actual Results:

division by zero

Expected Results:

same result for the int case

We use this on tables where we check if a value c2 is less than 10^{-6}. If so we print 10.0 else c1/c2.

Comment 17947

Date: 2012-11-16 12:23:40 +0100
From: @bartscheers

A work around would be
SELECT coalesce (CASE WHEN TRUE THEN -10. end, case when false then 0/0 END);

Comment 17994

Date: 2012-11-24 17:10:57 +0100
From: @njnes

added test case_evaluated_too_early.Bug-3186.sql

fixed exp_case_fixup to also handle this case

Comment 17995

Date: 2012-11-24 17:11:52 +0100
From: @njnes

Changeset 1a10469e62a2 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=1a10469e62a2

Changeset description:

fixed bug #3186

Comment 18370

Date: 2013-01-22 09:29:11 +0100
From: @sjoerdmullender

Oct2012-SP3 has been released.