Hi, Just adding another finding: Using 1 MERGE TABLE (on Mac) with 2 REMOTE TABLEs (on Linux [physically remote, in another network]) COUNT, MIN, MAX are fine but AVG, MEDIAN, QUANTILE etc. make the server crash. Using 1 MERGE TABLE (on Linux) with 1 REMOTE TABLE (on Linux [physically together, in the same network]) and 1 local TABLE, all the above functions are fine except for the occasional error. sql>select sys.median(doubleDataType) from xxxxxxx; (mapi:monetdb://monetdb@192.168.1.212/xxxxxxx) 'user.l2' undefined in:     (rmt3853_X_62_bat_oid_str:bat[:oid,:str],rmt3854_X_65_bat_oid_str:bat[:oid,:str],rmt3855_X_66_bat_oid_str:bat[:oid,:str ],rmt3856_X_67_bat_oid_str:bat[:oid,:str],rmt3857_X_68_bat_oid_dbl:bat[:oid,:dbl],rmt3858_X_70_bat_oid_dbl:bat[:oid,:d bl],rmt3859_X_71_bat_oid_dbl:bat[:oid,:dbl],rmt3860_X_72_bat_oid_dbl:bat[:oid,:dbl],rmt3861_X_73_bat_oid_dbl:bat[:oid ,:dbl],rmt3862_X_74_bat_oid_dbl:bat[:oid,:dbl],rmt3863_X_75_bat_oid_dbl:bat[:oid,:dbl],rmt3864_X_76_bat_oid_dbl:bat[: oid,:dbl],rmt3865_X_77_bat_oid_dbl:bat[:oid,:dbl],rmt3866_X_78_bat_oid_dbl:bat[:oid,:dbl],rmt3867_X_79_bat_oid_dbl:ba t[:oid,:dbl],rmt3868_X_80_bat_oid_dbl:bat[:oid,:dbl],rmt3869_X_81_bat_oid_dbl:bat[:oid,:dbl],rmt3870_X_82_bat_oid_dbl: bat[:oid,:dbl],rmt3871_X_83_bat_oid_dbl:bat[:oid,:dbl],rmt3872_X_84_bat_oid_dbl:bat[:oid,:dbl],rmt3873_X_85_bat_oid_d bl:bat[:oid,:dbl],rmt3874_X_86_bat_oid_dbl:bat[:oid,:dbl],rmt3875_X_87_bat_oid_dbl:bat[:oid,:dbl],rmt3876_X_88_bat_oid _dbl:bat[:oid,:dbl],rmt3877_X_89_bat_oid_dbl:bat[:oid,:dbl],rmt3878_X_90_bat_oid_dbl:bat[:oid,:dbl],rmt3879_X_91_bat_o id_dbl:bat[:oid,:dbl],rmt3880_X_92_bat_oid_dbl:bat[:oid,:dbl],rmt3881_X_93_bat_oid_dbl:bat[:oid,:dbl],rmt3882_X_94_ba t_oid_dbl:bat[:oid,:dbl],rmt3883_X_95_bat_oid_dbl:bat[:oid,:dbl],rmt3884_X_97_bat_oid_dbl:bat[:oid,:dbl],rmt3885_X_98_ bat_oid_dbl:bat[:oid,:dbl],rmt3886_X_99_bat_oid_dbl:bat[:oid,:dbl],rmt3887_X_100_bat_oid_dbl:bat[:oid,:dbl],rmt3888_X_ 101_bat_oid_dbl:bat[:oid,:dbl],rmt3889_X_103_bat_oid_dbl:bat[:oid,:dbl],rmt3890_X_104_bat_oid_dbl:bat[:oid,:dbl],rmt38 91_X_105_bat_oid_dbl:bat[:oid,:dbl],rmt3892_X_106_bat_oid_dbl:bat[:oid,:dbl],rmt3893_X_107_bat_oid_dbl:bat[:oid,:dbl],r mt3894_X_108_bat_oid_dbl:bat[:oid,:dbl],rmt3895_X_109_bat_oid_dbl:bat[:oid,:dbl],rmt3896_X_110_bat_oid_dbl:bat[:oid,: dbl],rmt3897_X_111_bat_oid_dbl:bat[:oid,:dbl],rmt3898_X_112_bat_oid_dbl:bat[:oid,:dbl],rmt3899_X_113_bat_oid_dbl:bat[: oid,:dbl],rmt3900_X_114_bat_oid_dbl:bat[:oid,:dbl],rmt3901_X_115_bat_oid_dbl:bat[:oid,:dbl],rmt3902_X_116_bat_oid_dbl: bat[:oid,:dbl],rmt3903_X_117_bat_oid_dbl:bat[:oid,:dbl],rmt3904_X_118_bat_oid_dbl:bat[:oid,:dbl],rmt3905_X_119_bat_oid _dbl:bat[:oid,:dbl],rmt3906_X_120_bat_oid_dbl:bat[:oid,:dbl],rmt3907_X_121_bat_oid_dbl:bat[:oid,:dbl],rmt3908_X_122_ba t_oid_dbl:bat[:oid,:dbl],rmt3909_X_123_bat_oid_dbl:bat[:oid,:dbl],rmt3910_X_124_bat_oid_dbl:bat[:oid,:dbl],rmt3911_X_12 5_bat_oid_dbl:bat[:oid,:dbl],rmt3912_X_126_bat_oid_bit:bat[:oid,:bit],rmt3913_X_128_bat_oid_bit:bat[:oid,:bit],rmt3914_X_ 130_bat_oid_oid:bat[:oid,:oid]) := user.l2(); Server version on Mac and Linux machines: MonetDB 5 server v11.21.5 "Jul2015" (64-bit, 64-bit oids, 128-bit integers) Thanks. Kind regards, Bart