gistfile1.txt

https://fiddle.clickhouse.com/afd6bac1-a4c1-4d51-bed8-2043012861c1

insert into function file(currentDatabase()||'_parallelize_output_from_storages_dedup_test.tsv', 'TSV')
select number, toString(arrayMap(x->cityHash64(x), range(number%11)))
from numbers(10000) order by cityHash64(number);

set min_insert_block_size_bytes=1000000,
    min_chunk_bytes_for_parallel_parsing = 10000;
set parallelize_output_from_storages = 0;

create table t (a Int64, b String) Engine=MergeTree order by tuple();
create table t1 as t Engine=MergeTree order by tuple();
system stop merges;

insert into t select * from file(currentDatabase()||'_parallelize_output_from_storages_dedup_test.tsv');
insert into t1 select * from file(currentDatabase()||'_parallelize_output_from_storages_dedup_test.tsv');

select count()
from
(select name, 
        rows r, 
        hash_of_uncompressed_files h, 
        hash_of_all_files ha,
        uncompressed_hash_of_compressed_files uhc
 from system.parts 
 where table like 't' and database = currentDatabase()) t
join 
(select name,
        rows r1, 
        hash_of_uncompressed_files h1, 
        hash_of_all_files ha1,
        uncompressed_hash_of_compressed_files uhc1
 from system.parts 
 where table like 't1' and database = currentDatabase()) t1
using name
where  h1 <> h or r1 <> r or ha1 <> ha or uhc1 <> uhc
format PrettyCompactMonoBlock;