```sql
CREATE TABLE t
(
   id Int64, 
   d String,
   p Map(String, String)
   
)
ENGINE = ReplacingMergeTree order by id settings index_granularity  = 0;


insert into t values (1,  's', {'a':'b'});

CH starts eating RAM until it crashes

the same with

insert into t select 1,  's', map('a','b');

```

{
    auto lock = lockParts();
    std::unordered_set<String> res;
    std::string_view prev_id;
    for (const auto & part : getDataPartsStateRange(DataPartState::Active))
    {
        if (prev_id == part->info.partition_id)
            continue;
        res.insert(part->info.partition_id);
        prev_id = part->info.partition_id;
    }
    return res;
}
MergeTreeData::DataPartsVector MergeTreeData::getDataPartsVectorForInternalUsage(