v.25.7Experimental Feature

256-bit bitmap stores the outgoing labels

The 256-bit bitmap stores the outgoing labels of a state ordered, but outgoing states are saved into disk in the order they appear in the hash table. Therefore, a label would point to a wrong next state while reading from disk. #82783 (Elmi Ahmadov).
Fixes the mismatch between the order of outgoing labels and outgoing states when reading from disk by ensuring correct mapping from labels to next states.

Why it matters

The feature addresses an issue where the 256-bit bitmap stores outgoing labels in an ordered manner, but the outgoing states are saved on disk based on their appearance in the hash table. This discrepancy causes labels to point to incorrect next states during disk read operations, leading to incorrect query results or processing errors.

How to use it

This fix is applied internally within ClickHouse and requires no additional configuration by users. Users should upgrade to the version including this patch to benefit from the corrected state mapping when reading data from disk.