| 1 | #pragma once |
|---|---|
| 2 | |
| 3 | #include <DataStreams/IBlockOutputStream.h> |
| 4 | #include <DataStreams/SquashingTransform.h> |
| 5 | |
| 6 | |
| 7 | namespace DB |
| 8 | { |
| 9 | |
| 10 | /** Merging consecutive blocks of stream to specified minimum size. |
| 11 | */ |
| 12 | class SquashingBlockOutputStream : public IBlockOutputStream |
| 13 | { |
| 14 | public: |
| 15 | SquashingBlockOutputStream(BlockOutputStreamPtr dst, Block header_, size_t min_block_size_rows, size_t min_block_size_bytes); |
| 16 | |
| 17 | Block getHeader() const override { return header; } |
| 18 | void write(const Block & block) override; |
| 19 | |
| 20 | void flush() override; |
| 21 | void writePrefix() override; |
| 22 | void writeSuffix() override; |
| 23 | |
| 24 | /// Don't write blocks less than specified size even when flush method was called by user. |
| 25 | void disableFlush() { disable_flush = true; } |
| 26 | |
| 27 | private: |
| 28 | BlockOutputStreamPtr output; |
| 29 | Block header; |
| 30 | |
| 31 | SquashingTransform transform; |
| 32 | bool all_written = false; |
| 33 | |
| 34 | void finalize(); |
| 35 | |
| 36 | bool disable_flush = false; |
| 37 | }; |
| 38 | |
| 39 | } |
| 40 |