Hi there, when I run 'count' on remote table I get a segfault on worker server: 'could not find L1.L1 NOT NULL as L1 L1.L1 Segmentation fault' Here is master(server/client) and worker (server/client), all are living on localhost (as it was shown in example https://www.monetdb.org/Documentation/Cookbooks/SQLrecipes/DistributedQueryP... ). master client [akravchenko@hnode1 ~]$ mclient -d mst Welcome to mclient, the MonetDB/SQL interactive terminal (Jun2016-SP1) Database: MonetDB v11.23.7 (Jun2016-SP1), 'mst' Type \q to quit, \? for a list of available commands auto commit mode: on sql>CREATE REMOTE TABLE t1 (i int) on 'mapi:monetdb://localhost:50001/rt1'; operation successful (1.357ms) sql>\d REMOTE TABLE sys.t1 sql>select * from t1; +------+ | i | +======+ | 11 | | 13 | +------+ 2 tuples (16.205ms) *sql>select count(*) from t1;* *an error occurred on connection: Connection lost* *sql>* worker client [akravchenko@hnode1 ~]$ mclient -d rt1 -p 50001 Welcome to mclient, the MonetDB/SQL interactive terminal (Jun2016-SP1) Database: MonetDB v11.23.7 (Jun2016-SP1), 'rt1' Type \q to quit, \? for a list of available commands auto commit mode: on sql>\d TABLE sys.t1 sql>select count(*) from t1; +------+ | L1 | +======+ | 2 | +------+ 1 tuple (0.594ms) worker server [akravchenko@hnode1 ~]$ mserver5 --dbpath=rt1 --set mapi_port=50001 # MonetDB 5 server v11.23.7 "Jun2016-SP1" # Serving database 'rt1', using 4 threads # Compiled for x86_64-redhat-linux-gnu/64bit with 64bit OIDs and 128bit integers dynamically linked # Found 31.357 GiB available main-memory. # Copyright (c) 1993-July 2008 CWI. # Copyright (c) August 2008-2016 MonetDB B.V., all rights reserved # Visit http://www.monetdb.org/ for further information # Listening for connection requests on mapi:monetdb://127.0.0.1:50001/ # MonetDB/SQL module loaded *>could not find L1.L1 NOT NULL as L1* *L1.L1* *Segmentation fault* master server [akravchenko@hnode1 ~]$ mserver5 --dbpath=mst # MonetDB 5 server v11.23.7 "Jun2016-SP1" # Serving database 'mst', using 4 threads # Compiled for x86_64-redhat-linux-gnu/64bit with 64bit OIDs and 128bit integers dynamically linked # Found 31.357 GiB available main-memory. # Copyright (c) 1993-July 2008 CWI. # Copyright (c) August 2008-2016 MonetDB B.V., all rights reserved # Visit http://www.monetdb.org/ for further information # Listening for connection requests on mapi:monetdb://127.0.0.1:50000/ # MonetDB/SQL module loaded Thank you, Anton