minor changes

src/DataTypes/DataTypeLowCardinality.cpp

@@ -584,9 +584,8 @@ void DataTypeLowCardinality::deserializeBinaryBulkWithMultipleStreamsImpl(
     size_t limit,
     DeserializeBinaryBulkSettings & settings,
     DeserializeBinaryBulkStatePtr & state,
-    SubstreamsCache * cache) const
+    SubstreamsCache * /* cache */) const
 {
-    UNUSED(cache);
     ColumnLowCardinality & low_cardinality_column = typeid_cast<ColumnLowCardinality &>(column);
 
     settings.path.push_back(Substream::DictionaryKeys);

src/Storages/ColumnsDescription.cpp

@@ -541,12 +541,12 @@ ColumnsDescription ColumnsDescription::parse(const String & str)
     return result;
 }
 
-void ColumnsDescription::addSubcolumns(const String & storage_name, const DataTypePtr & storage_type)
+void ColumnsDescription::addSubcolumns(const String & name_in_storage, const DataTypePtr & type_in_storage)
 {
-    for (const auto & subcolumn_name : storage_type->getSubcolumnNames())
+    for (const auto & subcolumn_name : type_in_storage->getSubcolumnNames())
     {
-        auto subcolumn = NameAndTypePair(storage_name, subcolumn_name,
+        auto subcolumn = NameAndTypePair(name_in_storage, subcolumn_name,
-            storage_type, storage_type->getSubcolumnType(subcolumn_name));
+            type_in_storage, type_in_storage->getSubcolumnType(subcolumn_name));
 
         if (has(subcolumn.name))
             throw Exception(ErrorCodes::ILLEGAL_COLUMN,
@@ -556,10 +556,10 @@ void ColumnsDescription::addSubcolumns(const String & storage_name, const DataTy
     }
 }
 
-void ColumnsDescription::removeSubcolumns(const String & storage_name, const DataTypePtr & storage_type)
+void ColumnsDescription::removeSubcolumns(const String & name_in_storage, const DataTypePtr & type_in_storage)
 {
-    for (const auto & subcolumn_name : storage_type->getSubcolumnNames())
+    for (const auto & subcolumn_name : type_in_storage->getSubcolumnNames())
-        subcolumns.erase(storage_name + "." + subcolumn_name);
+        subcolumns.erase(name_in_storage + "." + subcolumn_name);
 }
 
 Block validateColumnsDefaultsAndGetSampleBlock(ASTPtr default_expr_list, const NamesAndTypesList & all_columns, const Context & context)

src/Storages/ColumnsDescription.h

@@ -149,8 +149,8 @@ private:
     SubcolumnsContainer subcolumns;
 
     void modifyColumnOrder(const String & column_name, const String & after_column, bool first);
-    void addSubcolumns(const String & storage_name, const DataTypePtr & storage_type);
+    void addSubcolumns(const String & name_in_storage, const DataTypePtr & type_in_storage);
-    void removeSubcolumns(const String & storage_name, const DataTypePtr & storage_type);
+    void removeSubcolumns(const String & name_in_storage, const DataTypePtr & type_in_storage);
 };
 
 /// Validate default expressions and corresponding types compatibility, i.e.

src/Storages/MergeTree/IMergeTreeDataPart.cpp

@@ -193,11 +193,6 @@ std::optional<size_t> IMergeTreeDataPart::getColumnPosition(const String & colum
     return it->second;
 }
 
-std::optional<size_t> IMergeTreeDataPart::getColumnPosition(const NameAndTypePair & column) const
-{
-    return getColumnPosition(column.name);
-}
-
 DayNum IMergeTreeDataPart::getMinDate() const
 {
     if (storage.minmax_idx_date_column_pos != -1 && minmax_idx.initialized)

src/Storages/MergeTree/IMergeTreeDataPart.h

@@ -142,7 +142,6 @@ public:
     /// take place, you must take original name of column for this part from
     /// storage and pass it to this method.
     std::optional<size_t> getColumnPosition(const String & column_name) const;
-    std::optional<size_t> getColumnPosition(const NameAndTypePair & column) const;
 
     /// Returns the name of a column with minimum compressed size (as returned by getColumnSize()).
     /// If no checksums are present returns the name of the first physically existing column.

src/Storages/MergeTree/IMergeTreeReader.cpp

@@ -285,7 +285,7 @@ IMergeTreeReader::ColumnPosition IMergeTreeReader::findColumnForOffsets(const St
     {
         if (typeid_cast<const DataTypeArray *>(part_column.type.get()))
         {
-            auto position = data_part->getColumnPosition(part_column);
+            auto position = data_part->getColumnPosition(part_column.name);
             if (position && Nested::extractTableName(part_column.name) == table_name)
                 return position;
         }

src/Storages/MergeTree/MergeTreeDataPartCompact.cpp

@@ -124,7 +124,7 @@ void MergeTreeDataPartCompact::loadIndexGranularity()
 
 bool MergeTreeDataPartCompact::hasColumnFiles(const NameAndTypePair & column) const
 {
-    if (!getColumnPosition(column))
+    if (!getColumnPosition(column.name))
         return false;
 
     auto bin_checksum = checksums.files.find(DATA_FILE_NAME_WITH_EXTENSION);

src/Storages/MergeTree/MergeTreeDataPartInMemory.h

@@ -42,7 +42,7 @@ public:
         const MergeTreeIndexGranularity & computed_index_granularity) const override;
 
     bool isStoredOnDisk() const override { return false; }
-    bool hasColumnFiles(const NameAndTypePair & column) const override { return !!getColumnPosition(column); }
+    bool hasColumnFiles(const NameAndTypePair & column) const override { return !!getColumnPosition(column.name); }
     String getFileNameForColumn(const NameAndTypePair & /* column */) const override { return ""; }
     void renameTo(const String & new_relative_path, bool remove_new_dir_if_exists) const override;
     void makeCloneInDetached(const String & prefix, const StorageMetadataPtr & metadata_snapshot) const override;

src/Storages/MergeTree/MergeTreeReaderCompact.cpp

@@ -55,7 +55,7 @@ MergeTreeReaderCompact::MergeTreeReaderCompact(
         {
             auto column_from_part = getColumnFromPart(*name_and_type);
 
-            auto position = data_part->getColumnPosition(column_from_part);
+            auto position = data_part->getColumnPosition(column_from_part.name);
             if (!position && typeid_cast<const DataTypeArray *>(column_from_part.type.get()))
             {
                 /// If array of Nested column is missing in part,
@@ -140,7 +140,6 @@ size_t MergeTreeReaderCompact::readRows(size_t from_mark, bool continue_reading,
     while (read_rows < max_rows_to_read)
     {
         size_t rows_to_read = data_part->index_granularity.getMarkRows(from_mark);
-        std::unordered_map<String, IDataType::SubstreamsCache> caches;
 
         auto name_and_type = columns.begin();
         for (size_t pos = 0; pos < num_columns; ++pos, ++name_and_type)
@@ -154,8 +153,7 @@ size_t MergeTreeReaderCompact::readRows(size_t from_mark, bool continue_reading,
                 auto & column = res_columns[pos];
                 size_t column_size_before_reading = column->size();
 
-                readData(column_from_part, column, from_mark, *column_positions[pos],
+                readData(column_from_part, column, from_mark, *column_positions[pos], rows_to_read, read_only_offsets[pos]);
-                    rows_to_read, read_only_offsets[pos], caches[column_from_part.getNameInStorage()]);
 
                 size_t read_rows_in_column = column->size() - column_size_before_reading;
                 if (read_rows_in_column < rows_to_read)
@@ -189,8 +187,7 @@ size_t MergeTreeReaderCompact::readRows(size_t from_mark, bool continue_reading,
 
 void MergeTreeReaderCompact::readData(
     const NameAndTypePair & name_and_type, ColumnPtr & column,
-    size_t from_mark, size_t column_position, size_t rows_to_read,
+    size_t from_mark, size_t column_position, size_t rows_to_read, bool only_offsets)
-    bool only_offsets, IDataType::SubstreamsCache & cache)
 {
     const auto & [name, type] = name_and_type;
 
@@ -199,9 +196,6 @@ void MergeTreeReaderCompact::readData(
 
     auto buffer_getter = [&](const IDataType::SubstreamPath & substream_path) -> ReadBuffer *
     {
-        // if (cache.count(IDataType::getSubcolumnNameForStream(substream_path)))
-        //     return nullptr;
-
         if (only_offsets && (substream_path.size() != 1 || substream_path[0].type != IDataType::Substream::ArraySizes))
             return nullptr;
 
@@ -228,8 +222,6 @@ void MergeTreeReaderCompact::readData(
         type->deserializeBinaryBulkWithMultipleStreams(column, rows_to_read, deserialize_settings, state);
     }
 
-    UNUSED(cache);
-
     /// The buffer is left in inconsistent state after reading single offsets
     if (only_offsets)
         last_read_granule.reset();

src/Storages/MergeTree/MergeTreeReaderCompact.h

@@ -57,7 +57,7 @@ private:
     void seekToMark(size_t row_index, size_t column_index);
 
     void readData(const NameAndTypePair & name_and_type, ColumnPtr & column, size_t from_mark,
-        size_t column_position, size_t rows_to_read, bool only_offsets, IDataType::SubstreamsCache & cache);
+        size_t column_position, size_t rows_to_read, bool only_offsets);
 
     /// Returns maximal value of granule size in compressed file from @mark_ranges.
     /// This value is used as size of read buffer.

src/Storages/MergeTree/MergeTreeReaderWide.cpp

@@ -174,7 +174,7 @@ void MergeTreeReaderWide::readData(
     {
         return [&, stream_for_prefix](const IDataType::SubstreamPath & substream_path) -> ReadBuffer *
         {
-            /// If offsets for arrays have already been read. TODO
+            /// If substream have already been read.
             if (cache.count(IDataType::getSubcolumnNameForStream(substream_path)))
                 return nullptr;
 

src/Storages/StorageTinyLog.cpp

@@ -121,7 +121,7 @@ Chunk TinyLogSource::generate()
 {
     Block res;
 
-    if (is_finished || (!streams.empty() && streams.begin()->second->compressed.eof()))
+    if (is_finished || file_sizes.empty() || (!streams.empty() && streams.begin()->second->compressed.eof()))
     {
         /** Close the files (before destroying the object).
           * When many sources are created, but simultaneously reading only a few of them,
@@ -132,10 +132,6 @@ Chunk TinyLogSource::generate()
         return {};
     }
 
-    /// if there are no files in the folder, it means that the table is empty
-    if (storage.disk->isDirectoryEmpty(storage.table_path))
-        return {};
-
     std::unordered_map<String, IDataType::SubstreamsCache> caches;
     for (const auto & name_type : columns)
     {