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34 lines
635 B
C++
34 lines
635 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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/** Реализует реляционную операцию LIMIT.
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*/
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class LimitBlockInputStream : public IProfilingBlockInputStream
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{
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public:
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LimitBlockInputStream(BlockInputStreamPtr input_, size_t limit_, size_t offset_ = 0);
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Block readImpl();
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String getName() const { return "LimitBlockInputStream"; }
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BlockInputStreamPtr clone() { return new LimitBlockInputStream(input, limit, offset); }
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private:
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BlockInputStreamPtr input;
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size_t limit;
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size_t offset;
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size_t pos;
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};
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}
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