Date: 2013-03-29 12:42:46 +0100
From: milan <<milan.martak>>
To: SQL devs <>
Version: 11.15.3 (Feb2013-SP1)
CC: @njnes

Last updated: 2013-04-29 14:51:28 +0200

Comment 18655

Date: 2013-03-29 12:42:46 +0100
From: milan <<milan.martak>>

User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:19.0) Gecko/20100101 Firefox/19.0
Build Identifier:

The mclient will close connection when executing
SELECT as ... FROM GROUP BY
where is
extract(month from ) AS

merovingian.log shows there was database crash

2013-03-29 10:22:40 MSG merovingian[2446]: database 'zkdev1' (17036) was killed by signal SIGSEGV
2013-03-29 10:37:29 MSG merovingian[2446]: database 'zkdev1' has crashed after start on 2013-03-29 10:21:30, attempting restart, up min/avg/max: 2m/1d/1w, crash average: 1.00 1.00 0.60 (31-13=18)

this can be reproduced at any time - see the test case in "Steps to Reproduce"

Reproducible: Always

Steps to Reproduce:

CREATE VIEW mmtest_v AS SELECT date'2012-01-01' as period, 1 as quantity;

SELECT extract(month from period) as m, count(1) as cnt FROM mmtest_v GROUP BY m;

Actual Results:

Connection terminated + database killed by signal SIGSEGV

Expected Results:

query result, i.e.
m cnt

1 1

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffee3d5700 (LWP 25583)]
0x00007fffef493ffb in exp_alias_or_copy (sql=0x7fffe0005470, tname=0x0, cname=0x0, orel=0x0, old=0x7fffe00cd720, settname=0) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:185
185 ne = exp_column(sql->sa, nme, nme, exp_subtype(old), orel->card, has_nil(old), is_intern(old));
Missing separate debuginfos, use: debuginfo-install bzip2-libs-1.0.6-3.fc15.x86_64 cfitsio-3.280-2.fc16.x86_64 cyrus-sasl-lib-2.1.23-27.fc16.x86_64 geos-3.3.1-1.fc16.x86_64 glibc-2.14.90-24.fc16.9.x86_64 keyutils-libs-1.5.2-1.fc16.x86_64 krb5-libs-1.9.4-3.fc16.x86_64 libcom_err-1.41.14-2.fc15.x86_64 libcurl-7.21.7-8.fc16.x86_64 libgcc-4.6.3-2.fc16.x86_64 libidn-1.22-3.fc16.x86_64 libselinux-2.1.6-6.fc16.x86_64 libssh2-1.2.7-4.fc16.x86_64 libstdc++-4.6.3-2.fc16.x86_64 libuuid-2.20.1-2.3.fc16.x86_64 libxml2-2.7.8-8.fc16.x86_64 ncurses-libs-5.9-2.20110716.fc16.x86_64 nspr-4.9.4-1.fc16.x86_64 nss-3.14.1-3.fc16.x86_64 nss-softokn-freebl-3.14.1-3.fc16.x86_64 nss-util-3.14.1-1.fc16.x86_64 openldap-2.4.26-8.fc16.x86_64 openssl-1.0.0j-1.fc16.x86_64 pcre-8.12-9.fc16.x86_64 readline-6.2-2.fc16.x86_64 zlib-1.2.5-7.fc16.x86_64
(gdb) bt
0 0x00007fffef493ffb in exp_alias_or_copy (sql=0x7fffe0005470, tname=0x0, cname=0x0, orel=0x0, old=0x7fffe00cd720, settname=0) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:185
1 0x00007fffef4a2896 in rel_aggr (sql=0x7fffe0005470, rel=0x7fffee3d4900, distinct=0, aggrstr=0x7fffe00cc1e0 "count", args=0x7fffe00cc350, f=3) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:3771
2 0x00007fffef4a2d37 in rel_aggr (sql=0x7fffe0005470, rel=0x7fffee3d4900, se=0x7fffe00cc380, f=3) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:3832
3 0x00007fffef4a5992 in rel_value_exp2 (sql=0x7fffe0005470, rel=0x7fffee3d4900, se=0x7fffe00cc380, f=3, ek=..., is_last=0x7fffee3d4814) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:4543
4 0x00007fffef4a6267 in rel_value_exp (sql=0x7fffe0005470, rel=0x7fffee3d4900, se=0x7fffe00cc380, f=3, ek=...) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:4691
5 0x00007fffef4a634c in column_exp (sql=0x7fffe0005470, rel=0x7fffee3d4900, column_e=0x7fffe00cc430, f=3) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:4704
6 0x00007fffef4a65af in rel_column_exp (sql=0x7fffe0005470, rel=0x7fffee3d4900, column_e=0x7fffe00cc430, f=3) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:4748
7 0x00007fffef4a794b in rel_select_exp (sql=0x7fffe0005470, rel=0x7fffe00cd610, outer=0x0, sn=0x7fffe00cc7c0, ek=...) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:5059
8 0x00007fffef4a8ba7 in rel_query (sql=0x7fffe0005470, rel=0x0, sq=0x7fffe00cc7c0, toplevel=1, ek=...) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:5304
9 0x00007fffef4aa2fc in rel_subquery (sql=0x7fffe0005470, rel=0x0, sq=0x7fffe00cc7c0, ek=...) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:5660
10 0x00007fffef4aa393 in rel_selects (sql=0x7fffe0005470, s=0x7fffe00cc7c0) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_select.c:5671
11 0x00007fffef49363c in rel_semantic (sql=0x7fffe0005470, s=0x7fffe00cc7c0) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/server/rel_semantic.c:263
12 0x00007fffef41ccc6 in sql_symbol2relation (c=0x7fffe0005470, sym=0x7fffe00cc7c0) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/backends/monet5/sql.mx:1723
13 0x00007fffef3e93ab in SQLparser (c=0x648b28) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/sql/backends/monet5/sql_scenario.c:1666
14 0x00007ffff7a73367 in runPhase (c=0x648b28, phase=1) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/monetdb5/mal/mal_scenario.c:522
15 0x00007ffff7a7365f in runScenarioBody (c=0x648b28) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/monetdb5/mal/mal_scenario.c:587
16 0x00007ffff7a73826 in runScenario (c=0x648b28) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/monetdb5/mal/mal_scenario.c:616
17 0x00007ffff7a748a0 in MSserveClient (dummy=0x648b28) at /ufs/manegold//Monet/HG/Feb2013/source/MonetDB/monetdb5/mal/mal_session.c:431
18 0x0000003cf3c07d90 in start_thread () from /lib64/libpthread.so.0
19 0x0000003cf30f119d in clone () from /lib64/libc.so.6
(gdb) li
180 } else if (!cname) {
181 char name[16], *nme;
182 nme = number2name(name, 16, ++sql->label);
183
184 exp_setname(sql->sa, old, nme, nme);
185 ne = exp_column(sql->sa, nme, nme, exp_subtype(old), orel->card, has_nil(old), is_intern(old));
186 ne->p = prop_copy(sql->sa, old->p);
187 return ne;
188 } else if (cname && !old->name) {
189 exp_setname(sql->sa, old, tname, cname);
(gdb) p sql
$1 = (mvc *) 0x7fffe0005470
(gdb) p sql->sa
$2 = (sql_allocator *) 0x7fffe007aeb0
(gdb) p *sql
$3 = {errstr = "\000ELECT: identifier 'm' unknown\000wn", '\000' <repeats 8158 times>, sa = 0x7fffe007aeb0, qc = 0x7fffe00075d0, clientid = 1, scanner = {rs = 0x7fffe8006c30, ws = 0x7fffe8004b20, log = 0x0, yynext = 0, yylast = 259, yysval = 80, yyval = 377, yycur = 81, yybak = 10 '\n',
as = 0, key = 203, started = 1, mode = LINE_N, schema = 0x0}, params = 0x0, vars = 0x7fffe0007610, topvars = 9, sizevars = 32, frame = 1, use_views = 0, args = 0x7fffe0007e30, argc = 1, argmax = 32, sym = 0x7fffe00cc7c0, point_query = 0, user_id = 3, role_id = 3, last_id = -1,
timezone = 3600000, cache = 100, caching = 100, history = 0, reply_size = -1, sizeheader = 0, debug = 0, emode = 0 '\000', emod = 0 '\000', session = 0x7fffe0007f50, type = 0, label = 1, cascade_action = 0x0, opt_stats = {0, 0, 0, 0, 0, 0, 0, 0}, result_id = 1, results = 0x0, times = {
tms_utime = 0, tms_stime = 0, tms_cutime = 0, tms_cstime = 0}, Tparse = 0}
(gdb) p *sql->sa
$4 = {size = 64, nr = 1, blks = 0x7fffe0082800, used = 6256, usedmem = 111904}
(gdb) p nme
$5 = 0x7fffee3d452d "L1"
(gdb) p old
$6 = (sql_exp *) 0x7fffe00cd720
(gdb) p *old
$7 = {type = e_atom, name = 0x7fffe00cd7b0 "L1", rname = 0x7fffe00cd7c0 "L1", l = 0x0, r = 0x0, f = 0x0, flag = 0, card = 1 '\001', tpe = {type = 0x19eb3b0, digits = 8, scale = 0, comp_type = 0x0}, used = 0, p = 0x0}
(gdb) p orel
$8 = (sql_rel *) 0x0

Comment 18656

Date: 2013-03-29 12:46:13 +0100
From: milan <<milan.martak>>

Created attachment 191
gdb trace created by Stefan M.

Attached file: gdb_trace_segfault_view_select.txt (text/plain, 6406 bytes)
Description: gdb trace created by Stefan M.

Comment 18657

Date: 2013-03-29 12:49:31 +0100
From: @njnes

fixed crash in exp_alias_or_copy, there is no enclosing orel in this case.

Comment 18658

Date: 2013-03-29 12:50:20 +0100
From: MonetDB Mercurial Repository <>

Changeset 329bbb4c5564 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=329bbb4c5564

Changeset description:

fixed bug #3264