drop table if exists nested_map; create table nested_map (d default today(), k UInt64, payload default rand(), SomeMap Nested(ID UInt32, Num Int64)) engine=SummingMergeTree(d, k, 8192); insert into nested_map (k, `SomeMap.ID`, `SomeMap.Num`) values (0,[1],[100]),(1,[1],[100]),(2,[1],[100]),(3,[1,2],[100,150]); insert into nested_map (k, `SomeMap.ID`, `SomeMap.Num`) values (0,[2],[150]),(1,[1],[150]),(2,[1,2],[150,150]),(3,[1],[-100]); optimize table nested_map; select `SomeMap.ID`, `SomeMap.Num` from nested_map; drop table nested_map; drop table if exists nested_map_explicit; create table nested_map_explicit (d default today(), k UInt64, SomeIntExcluded UInt32, SomeMap Nested(ID UInt32, Num Int64)) engine=SummingMergeTree(d, k, 8192, (SomeMap)); insert into nested_map_explicit (k, `SomeIntExcluded`, `SomeMap.ID`, `SomeMap.Num`) values (0, 20, [1],[100]),(1, 20, [1],[100]),(2, 20, [1],[100]),(3, 20, [1,2],[100,150]); insert into nested_map_explicit (k, `SomeIntExcluded`, `SomeMap.ID`, `SomeMap.Num`) values (0, 20, [2],[150]),(1, 20, [1],[150]),(2, 20, [1,2],[150,150]),(3, 20, [1],[-100]); optimize table nested_map_explicit; select `SomeIntExcluded`, `SomeMap.ID`, `SomeMap.Num` from nested_map_explicit; drop table nested_map_explicit;