Within a transaction, \d after an error causes mclient to exit

[monetdb-team]

Date: 2018-08-02 14:44:45 +0200
From: @yzchang
To: clients devs <>
Version: 11.29.7 (Mar2018-SP1)

Last updated: 2018-08-31 13:23:17 +0200

Comment 26585

Date: 2018-08-02 14:44:45 +0200
From: @yzchang

After START TRANSACTION, executing an arbitrary query which returns an error, and then executing a '\d' command will trigger the following code (dump.c:2535):

     if (mapi_error(mid)) {
             mapi_explain(mid, stderr);
             exit(2);
     }

So, mclient just exits.

E.g. try the following:
sql>start transaction; seledaf;
auto commit mode: off
syntax error, unexpected IDENT in: "seledaf"
sql>\d

Comment 26592

Date: 2018-08-08 11:03:54 +0200
From: MonetDB Mercurial Repository <>

Changeset 1ae81b91cb04 made by Sjoerd Mullender sjoerd@acm.org in the MonetDB repo, refers to this bug.

For complete details, see https//devmonetdborg/hg/MonetDB?cmd=changeset;node=1ae81b91cb04

Changeset description:

Do not exit from a library function; not even a very local one.
Do some proper error handling when getting the clause to retrieve
comments.
This fixes bug #6637.