From 7c4d24ce398c225b7f15a29796ffad73c4ae310b Mon Sep 17 00:00:00 2001 From: Alexey Milovidov Date: Wed, 17 Oct 2018 00:25:45 +0300 Subject: [PATCH] Added comment [#CLICKHOUSE-3901] --- dbms/src/Storages/MergeTree/MergedBlockOutputStream.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/dbms/src/Storages/MergeTree/MergedBlockOutputStream.h b/dbms/src/Storages/MergeTree/MergedBlockOutputStream.h index 8d9e6bc8fb4..a3f6a025c31 100644 --- a/dbms/src/Storages/MergeTree/MergedBlockOutputStream.h +++ b/dbms/src/Storages/MergeTree/MergedBlockOutputStream.h @@ -156,6 +156,8 @@ class MergedColumnOnlyOutputStream final : public IMergedBlockOutputStream { public: /// skip_offsets: used when ALTERing columns if we know that array offsets are not altered. + /// Pass empty 'already_written_offset_columns' first time then and pass the same object to subsequent instances of MergedColumnOnlyOutputStream + /// if you want to serialize elements of Nested data structure in different instances of MergedColumnOnlyOutputStream. MergedColumnOnlyOutputStream( MergeTreeData & storage_, const Block & header_, String part_path_, bool sync_, CompressionSettings compression_settings, bool skip_offsets_,