String VS Array(UInt8)

gistfile1.txt

create table pass (i UInt64,  S String, P Array(UInt8)) Engine=MergeTree order by i;
insert into pass select number, arrayStringConcat(arrayMap(i -> char(i*number%255), range(10)),''), arrayMap(i -> i*number%255, range(30)) from numbers(10000000);

┌─database─┬─table─┬─column─┬─compressed─┬─uncompressed─┐
│ dw       │ pass  │ i      │ 38.19 MiB  │ 76.29 MiB    │
│ dw       │ pass  │ P      │ 10.30 MiB  │ 362.40 MiB   │
│ dw       │ pass  │ S      │ 3.72 MiB   │ 104.90 MiB   │
└──────────┴───────┴────────┴────────────┴──────────────┘


clickhouse-benchmark --database default -c 16 <<< "select count() from pass where S='AAAAAA'"
QPS: 136.703

clickhouse-benchmark --database default -c 16 <<< "select count() from pass where P=[65,65,65,65,65,65]"
QPS: 70.801


--- CODEC NONE ---

create table pass (i UInt64,  S String CODEC(NONE), P Array(UInt8) CODEC(NONE)) Engine=MergeTree order by i;
insert into pass select number, arrayStringConcat(arrayMap(i -> char(i*number%255), range(10)),''), arrayMap(i -> i*number%255, range(30)) from numbers(10000000);

┌─database─┬─table─┬─column─┬─compressed─┬─uncompressed─┐
│ dw       │ pass  │ P      │ 362.45 MiB │ 362.40 MiB   │
│ dw       │ pass  │ S      │ 104.93 MiB │ 104.90 MiB   │
│ dw       │ pass  │ i      │ 20.30 MiB  │ 76.29 MiB    │
└──────────┴───────┴────────┴────────────┴──────────────┘

clickhouse-benchmark --database default -c 16 <<< "select count() from pass where S='AAAAAA'"
QPS: 49.017
clickhouse-benchmark --database default -c 16 <<< "select count() from pass where P=[65,65,65,65,65,65]"
QPS: 12.449