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41 lines
696 B
C++
41 lines
696 B
C++
#pragma once
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#include <Poco/SharedPtr.h>
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#include <DB/DataStreams/IProfilingBlockInputStream.h>
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namespace DB
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{
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using Poco::SharedPtr;
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/** Поток блоков, из которого можно прочитать один блок.
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*/
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class OneBlockInputStream : public IProfilingBlockInputStream
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{
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public:
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OneBlockInputStream(Block & block_) : block(block_), has_been_read(false) {}
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String getName() const { return "OneBlockInputStream"; }
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BlockInputStreamPtr clone() { return new OneBlockInputStream(block); }
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protected:
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Block readImpl()
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{
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if (has_been_read)
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return Block();
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has_been_read = true;
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return block;
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}
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private:
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Block block;
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bool has_been_read;
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};
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}
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