Method execute

src/Interpreters/InterpreterKillQueryQuery.cpp:206–427

BlockIO InterpreterKillQueryQuery::execute()
{
    const auto & query = query_ptr->as<ASTKillQueryQuery &>();

    if (!query.cluster.empty())
    {
        DDLQueryOnClusterParams params;
        params.access_to_check = getRequiredAccessForDDLOnCluster();
        return executeDDLQueryOnCluster(query_ptr, getContext(), params);
    }

    BlockIO res_io;
    switch (query.type)
    {
    case ASTKillQueryQuery::Type::Query:
    {
        Block processes_block = getSelectResult("query_id, user, query", "system.processes");
        if (processes_block.empty())
            return res_io;

        ProcessList & process_list = getContext()->getProcessList();
        QueryDescriptors queries_to_stop = extractQueriesExceptMeAndCheckAccess(processes_block, getContext());

        auto header = processes_block.cloneEmpty();
        header.insert(0, {ColumnString::create(), std::make_shared<DataTypeString>(), "kill_status"});

        if (!query.sync || query.test)
        {
            MutableColumns res_columns = header.cloneEmptyColumns();
            for (const auto & query_desc : queries_to_stop)
            {
                if (!query.test)
                    LOG_DEBUG(getLogger("KillQuery"), "Will kill query {} (asynchronously)", query_desc.query_id);
                auto code = (query.test) ? CancellationCode::Unknown : process_list.sendCancelToQuery(query_desc.query_id, query_desc.user);
                insertResultRow(query_desc.source_num, code, processes_block, header, res_columns);
            }

            res_io.pipeline = QueryPipeline(std::make_shared<SourceFromSingleChunk>(std::make_shared<const Block>(header.cloneWithColumns(std::move(res_columns)))));
        }
        else
        {
            res_io.pipeline = QueryPipeline(std::make_shared<SyncKillQuerySource>(
                process_list, std::move(queries_to_stop), std::move(processes_block), std::make_shared<const Block>(header)));
        }

        break;
    }
    case ASTKillQueryQuery::Type::Mutation:
    {
        Block mutations_block = getSelectResult("database, table, mutation_id, command", "system.mutations");
        if (mutations_block.empty())
            return res_io;

        const ColumnString & database_col = typeid_cast<const ColumnString &>(*mutations_block.getByName("database").column);
        const ColumnString & table_col = typeid_cast<const ColumnString &>(*mutations_block.getByName("table").column);
        const ColumnString & mutation_id_col = typeid_cast<const ColumnString &>(*mutations_block.getByName("mutation_id").column);
        const ColumnString & command_col = typeid_cast<const ColumnString &>(*mutations_block.getByName("command").column);