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This commit is contained in:
alesapin 2020-05-14 13:30:53 +03:00
parent ab760846c2
commit 316773d853
1 changed files with 4 additions and 2 deletions
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6
src/Storages/MergeTree/MergeTreeDataMergerMutator.h
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@ -143,8 +143,10 @@ private:
MutationCommands & for_interpreter,
MutationCommands & for_file_renames);
/// Apply commands to source_part i.e. remove some columns in source_part
/// and return set of files, that have to be removed from filesystem and checksums
/// Apply commands to source_part i.e. remove and rename some columns in
/// source_part and return set of files, that have to be removed or renamed
/// from filesystem and in-memory checksums. Ordered result is important,
/// because we can apply renames that affects each other: x -> z, y -> x.
static NameToNameVector collectFilesForRenames(MergeTreeData::DataPartPtr source_part, const MutationCommands & commands_for_removes, const String & mrk_extension);
/// Files, that we don't need to remove and don't need to hardlink, for example columns.txt and checksums.txt.