RELEASE SAVEPOINT after ALTER TABLE crashes mserver5

[monetdb-team]

Date: 2016-05-19 12:17:30 +0200
From: @yzchang
To: SQL devs <>
Version: 11.21.19 (Jul2015-SP4)
CC: @njnes, @yzchang

Last updated: 2016-06-23 10:24:25 +0200

Comment 22151

Date: 2016-05-19 12:17:30 +0200
From: @yzchang

The "RELEASE SAVEPOIN ..." query below causes a SEGFAULT in
0x00007fffe8a6ccfa in tr_merge_dbat (tr=0x7fffcc10c760, tdb=0x0)
at /net/toulouse/export/scratch2/zhang/monet-source/Jun2016/sql/storage/bat/bat_storage.c:2089
2089 if (tdb->cached) {

CREATE TABLE test (a int);
START TRANSACTION ;
SAVEPOINT failsafe;
ALTER TABLE test ADD COLUMN b int;
RELEASE SAVEPOINT failsafe;
COMMIT;

The crash seems to have been particularly caused by the use of ALTER TABLE, since it doesn't happen after, e.g., an "INSERT INTO test...".

Comment 22152

Date: 2016-05-19 14:53:42 +0200
From: MonetDB Mercurial Repository <>

Changeset 19ada2e374e8 made by Jennie Zhang y.zhang@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=19ada2e374e8

Changeset description:

Added test for bug #4010

Comment 22154

Date: 2016-05-19 16:14:55 +0200
From: @yzchang

Just for the records, next to ALTER TABLE, an UPDATE causes mserver5 to crash at the same place. For instance, these queries:

drop table t;
create table t (i int, j int);
insert into t values (10, 20);
start transaction;
savepoint sp;
UPDATE t set i = 42 where j = 20;
release savepoint sp;
commit;
select * from t;

Comment 22155

Date: 2016-05-19 16:23:34 +0200
From: MonetDB Mercurial Repository <>

Changeset a40033240ec6 made by Jennie Zhang y.zhang@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=a40033240ec6

Changeset description:

Added a second test cast for Bug #4010

Comment 22174

Date: 2016-05-24 23:11:33 +0200
From: @njnes

fixed

Comment 22180

Date: 2016-05-26 14:19:04 +0200
From: @yzchang

Just for the record, this bug was fixed by http//devmonetdborg/hg/MonetDB?cmd=changeset;node=2eaffa87695a

Comment 22181

Date: 2016-05-26 16:49:06 +0200
From: MonetDB Mercurial Repository <>

Changeset 17d2b854e0fa made by Jennie Zhang y.zhang@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=17d2b854e0fa

Changeset description:

Added test for bug #4010

Comment 22182

Date: 2016-05-26 16:50:04 +0200
From: MonetDB Mercurial Repository <>

Changeset c1144dfa2ca0 made by Jennie Zhang y.zhang@cwi.nl in the MonetDB repo, refers to this bug.

For complete details, see http//devmonetdborg/hg/MonetDB?cmd=changeset;node=c1144dfa2ca0

Changeset description:

Added a second test cast for Bug #4010

Comment 22183

Date: 2016-05-26 16:52:25 +0200
From: @yzchang

That was just back porting tests accidentally added in Jun2016 to Jul2015