1 | #include <DataStreams/SquashingBlockInputStream.h> |
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2 | |
3 | |
4 | namespace DB |
5 | { |
6 | |
7 | SquashingBlockInputStream::SquashingBlockInputStream( |
8 | const BlockInputStreamPtr & src, size_t min_block_size_rows, size_t min_block_size_bytes, bool reserve_memory) |
9 | : header(src->getHeader()), transform(min_block_size_rows, min_block_size_bytes, reserve_memory) |
10 | { |
11 | children.emplace_back(src); |
12 | } |
13 | |
14 | |
15 | Block SquashingBlockInputStream::readImpl() |
16 | { |
17 | if (all_read) |
18 | return {}; |
19 | |
20 | while (true) |
21 | { |
22 | Block block = children[0]->read(); |
23 | if (!block) |
24 | all_read = true; |
25 | |
26 | SquashingTransform::Result result = transform.add(block.mutateColumns()); |
27 | if (result.ready) |
28 | { |
29 | if (result.columns.empty()) |
30 | return {}; |
31 | return header.cloneWithColumns(std::move(result.columns)); |
32 | } |
33 | } |
34 | } |
35 | |
36 | } |
37 |