When I queried `system.metrics` table, I found some negative values which hint to some potential internal overflows.

```
SELECT *
FROM system.metrics
FORMAT Vertical

...

Row 31:
───────
metric:      MemoryTrackingInBackgroundProcessingPool
value:       -580863171
description: Total amount of memory (bytes) allocated in background processing pool (that is dedicated for backround merges, mutations and fetches). Note that this value may include a drift when the memory was allocated in a context of background processing pool and freed in other context or vice-versa. This happens naturally due to caches for tables indexes and doesn't indicate memory leaks.

Row 32:
───────
metric:      MemoryTrackingInBackgroundMoveProcessingPool
value:       0
description: Total amount of memory (bytes) allocated in background processing pool (that is dedicated for backround moves). Note that this value may include a drift when the memory was allocated in a context of background processing pool and freed in other context or vice-versa. This happens naturally due to caches for tables indexes and doesn't indicate memory leaks.

Row 33:
───────
metric:      MemoryTrackingInBackgroundSchedulePool
value:       -4461308831
description: Total amount of memory (bytes) allocated in background schedule pool (that is dedicated for bookkeeping tasks of Replicated tables).

...

56 rows in set. Elapsed: 0.003 sec.
```

Server version: 20.8.2.3.
{
    return input_blocks_reader;
}
void Context::resetInputCallbacks()
{
    if (input_initializer_callback)
        input_initializer_callback = {};
    if (input_blocks_reader)
        input_blocks_reader = {};
}
StorageID Context::resolveStorageID(StorageID storage_id, StorageNamespace where) const
{
    if (storage_id.uuid != UUIDHelpers::Nil)
        return storage_id;
    StorageID resolved = StorageID::createEmpty();
    std::optional<Exception> exc;
    {
        auto lock = getLock();
        resolved = resolveStorageIDImpl(std::move(storage_id), where, &exc);
    }
    if (exc)
        throw Exception(*exc);
    if (!resolved.hasUUID() && resolved.database_name != DatabaseCatalog::TEMPORARY_DATABASE)
        resolved.uuid = DatabaseCatalog::instance().getDatabase(resolved.database_name)->tryGetTableUUID(resolved.table_name);
    return resolved;
}
StorageID Context::tryResolveStorageID(StorageID storage_id, StorageNamespace where) const