DistributedBlockOutputStream: add more comments

This commit is contained in:
Azat Khuzhin 2021-01-17 12:50:37 +03:00
parent b725e1d131
commit a6631287a7

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@ -655,6 +655,8 @@ void DistributedBlockOutputStream::writeToShard(const Block & block, const std::
NativeBlockOutputStream stream{compress, DBMS_TCP_PROTOCOL_VERSION, block.cloneEmpty()};
/// Prepare the header.
/// See also readDistributedHeader() in DirectoryMonitor (for reading side)
///
/// We wrap the header into a string for compatibility with older versions:
/// a shard will able to read the header partly and ignore other parts based on its version.
WriteBufferFromOwnString header_buf;