Hi, I run mserver5 in standalone mode. The SQL input works fine but the corresponding MAL input fails. See below for the details. - MonetDB version 11.17.21 - Command line mserver5 --dbpath=${DBPATH} --set mapi_open=false --set mapi_port=0 --set single-user=yes --set gdk_nr_threads=1--set max_clients=1 --set sql_optimizer=default_pipe --set monet_daemon=no < ${INPUT} - Database TPC-H (scale factor: 1) - The SQL input: sql.start(); select count(*) from supplier, nation, region where r_name = 'EUROPE' and r_regionkey = n_regionkey and s_nationkey = n_nationkey; - The MAL input: (I use "explain" to get the MAL plan) sql.init(); function user.s0_0{autoCommit=true}(A0:str):void; X_3 := sql.mvc(); X_4:bat[:oid,:oid] := sql.tid(X_3,"sys","nation"); X_7 := sql.bind_idxbat(X_3,"sys","nation","nation_n_regionkey_fkey",0); (X_10,r1_10) := sql.bind_idxbat(X_3,"sys","nation","nation_n_regionkey_fkey",2); X_13 := sql.bind_idxbat(X_3,"sys","nation","nation_n_regionkey_fkey",1); X_15 := sql.projectdelta(X_4,X_7,X_10,r1_10,X_13); X_18 := sql.bind(X_3,"sys","region","r_name",0); X_16:bat[:oid,:oid] := sql.tid(X_3,"sys","region"); X_72 := algebra.subselect(X_18,X_16,A0,A0,true,true,false); (X_20,r1_21) := sql.bind(X_3,"sys","region","r_name",2); X_73 := algebra.subselect(r1_21,A0,A0,true,true,false); X_22 := sql.bind(X_3,"sys","region","r_name",1); X_74 := algebra.subselect(X_22,X_16,A0,A0,true,true,false); X_23 := sql.subdelta(X_72,X_16,X_20,X_73,X_74); X_25 := X_23; (X_26,r1_30) := algebra.join(X_15,X_25); X_28 := algebra.leftfetchjoin(X_26,X_4); X_29:bat[:oid,:oid] := sql.tid(X_3,"sys","supplier"); X_31 := sql.bind_idxbat(X_3,"sys","supplier","supplier_s_nationkey_fkey",0); (X_33,r1_37) := sql.bind_idxbat(X_3,"sys","supplier","supplier_s_nationkey_fkey",2); X_36 := sql.bind_idxbat(X_3,"sys","supplier","supplier_s_nationkey_fkey",1); X_37 := sql.projectdelta(X_29,X_31,X_33,r1_37,X_36); (X_38,r1_43) := algebra.join(X_28,X_37); X_40 := algebra.leftfetchjoin(X_38,X_28); X_41 := aggr.count(X_40); sql.exportValue(1,".L1","L1","wrd",64,0,6,X_41,""); end s0_0; user.s0_0("EUROPE"); mserver5 reports the following error message when running the MAL input: !TypeException:user.s0_0[23]:'algebra.join' undefined in: (X_38:any, r1_43:any) := algebra.join(X_28:bat[:oid,:oid], X_37:bat[:oid,:any]) It seems to me that X_28 is not in the right format. But I have no idea how it could happen and how to make it correct. Any thoughts on this will be much appreciated. Thanks! -Qing