#pragma once #include #include #include namespace DB { class ReadBuffer; class WriteBuffer; /** More information about the block. */ struct BlockInfo { /** is_overflows: * After running GROUP BY ... WITH TOTALS with the max_rows_to_group_by and group_by_overflow_mode = 'any' settings, * a row is inserted in the separate block with aggregated values that have not passed max_rows_to_group_by. * If it is such a block, then is_overflows is set to true for it. */ /** bucket_num: * When using the two-level aggregation method, data with different key groups are scattered across different buckets. * In this case, the bucket number is indicated here. It is used to optimize the merge for distributed aggregation. * Otherwise -1. */ #define APPLY_FOR_BLOCK_INFO_FIELDS(M) \ M(bool, is_overflows, false, 1) \ M(Int32, bucket_num, -1, 2) #define DECLARE_FIELD(TYPE, NAME, DEFAULT, FIELD_NUM) \ TYPE NAME = DEFAULT; APPLY_FOR_BLOCK_INFO_FIELDS(DECLARE_FIELD) #undef DECLARE_FIELD /// Write the values in binary form. NOTE: You could use protobuf, but it would be overkill for this case. void write(WriteBuffer & out) const; /// Read the values in binary form. void read(ReadBuffer & in); }; /// Block extension to support delayed defaults. AddingDefaultsBlockInputStream uses it to replace missing values with column defaults. class BlockMissingValues { public: using RowsBitMask = std::vector; /// a bit per row for a column /// Get mask for column, column_idx is index inside corresponding block const RowsBitMask & getDefaultsBitmask(size_t column_idx) const; /// Check that we have to replace default value at least in one of columns bool hasDefaultBits(size_t column_idx) const; void setBit(size_t column_idx, size_t row_idx); bool empty() const { return rows_mask_by_column_id.empty(); } size_t size() const { return rows_mask_by_column_id.size(); } void clear() { rows_mask_by_column_id.clear(); } private: using RowsMaskByColumnId = std::unordered_map; /// If rows_mask_by_column_id[column_id][row_id] is true related value in Block should be replaced with column default. /// It could contain less columns and rows then related block. RowsMaskByColumnId rows_mask_by_column_id; }; }