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Update Pipe.cpp

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Nikolai Kochetov 2021-04-20 16:53:28 +03:00 committed by GitHub
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commit bc5b34fb6b
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src/Processors/Pipe.cpp
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@ -251,6 +251,9 @@ static Pipes removeEmptyPipes(Pipes pipes)
return res;
}
/// Calculate comon header for pipes.
/// This function is needed only to remove ColumnConst from common header in case if some columns are const, and some not.
/// E.g. if the first header is `x, const y, const z` and the second is `const x, y, const z`, the common header will be `x, y, const z`.
static Block getCommonHeader(const Pipes & pipes)
{
Block res;