Method transformHeader

src/Processors/Transforms/JoiningTransform.cpp:30–39

}

Block JoiningTransform::transformHeader(Block header, const JoinPtr & join)
{
    LOG_TEST(getLogger("JoiningTransform"), "Before join block: '{}'", header.dumpStructure());
    join->checkTypesOfKeys(header);
    join->initialize(header);
    header = join->joinBlock(std::move(header))->next().block;
    materializeBlockInplace(header);
    LOG_TEST(getLogger("JoiningTransform"), "After join block: '{}'", header.dumpStructure());
    return header;
}

JoiningTransform::JoiningTransform(
    SharedHeader input_header,