1 | #include <iostream> |
2 | #include <iomanip> |
3 | |
4 | #include <IO/WriteBufferFromOStream.h> |
5 | #include <IO/ReadHelpers.h> |
6 | |
7 | #include <Storages/System/StorageSystemNumbers.h> |
8 | |
9 | #include <DataStreams/LimitBlockInputStream.h> |
10 | #include <DataStreams/ExpressionBlockInputStream.h> |
11 | #include <Formats/FormatFactory.h> |
12 | #include <DataStreams/copyData.h> |
13 | |
14 | #include <DataTypes/DataTypesNumber.h> |
15 | |
16 | #include <Parsers/ParserSelectQuery.h> |
17 | #include <Parsers/parseQuery.h> |
18 | |
19 | #include <Interpreters/SyntaxAnalyzer.h> |
20 | #include <Interpreters/ExpressionAnalyzer.h> |
21 | #include <Interpreters/ExpressionActions.h> |
22 | #include <Interpreters/Context.h> |
23 | |
24 | |
25 | int main(int argc, char ** argv) |
26 | try |
27 | { |
28 | using namespace DB; |
29 | |
30 | size_t n = argc == 2 ? parse<UInt64>(argv[1]) : 10ULL; |
31 | |
32 | std::string input = "SELECT number, number / 3, number * number" ; |
33 | |
34 | ParserSelectQuery parser; |
35 | ASTPtr ast = parseQuery(parser, input.data(), input.data() + input.size(), "" , 0); |
36 | |
37 | Context context = Context::createGlobal(); |
38 | context.makeGlobalContext(); |
39 | |
40 | NamesAndTypesList source_columns = {{"number" , std::make_shared<DataTypeUInt64>()}}; |
41 | auto syntax_result = SyntaxAnalyzer(context, {}).analyze(ast, source_columns); |
42 | SelectQueryExpressionAnalyzer analyzer(ast, syntax_result, context); |
43 | ExpressionActionsChain chain(context); |
44 | analyzer.appendSelect(chain, false); |
45 | analyzer.appendProjectResult(chain); |
46 | chain.finalize(); |
47 | ExpressionActionsPtr expression = chain.getLastActions(); |
48 | |
49 | StoragePtr table = StorageSystemNumbers::create("numbers" , false); |
50 | |
51 | Names column_names; |
52 | column_names.push_back("number" ); |
53 | |
54 | QueryProcessingStage::Enum stage = table->getQueryProcessingStage(context); |
55 | |
56 | BlockInputStreamPtr in; |
57 | in = table->read(column_names, {}, context, stage, 8192, 1)[0]; |
58 | in = std::make_shared<ExpressionBlockInputStream>(in, expression); |
59 | in = std::make_shared<LimitBlockInputStream>(in, 10, std::max(static_cast<Int64>(0), static_cast<Int64>(n) - 10)); |
60 | |
61 | WriteBufferFromOStream out1(std::cout); |
62 | BlockOutputStreamPtr out = FormatFactory::instance().getOutput("TabSeparated" , out1, expression->getSampleBlock(), context); |
63 | |
64 | { |
65 | Stopwatch stopwatch; |
66 | stopwatch.start(); |
67 | |
68 | copyData(*in, *out); |
69 | |
70 | stopwatch.stop(); |
71 | std::cout << std::fixed << std::setprecision(2) |
72 | << "Elapsed " << stopwatch.elapsedSeconds() << " sec." |
73 | << ", " << n / stopwatch.elapsedSeconds() << " rows/sec." |
74 | << std::endl; |
75 | } |
76 | |
77 | return 0; |
78 | } |
79 | catch (const DB::Exception & e) |
80 | { |
81 | std::cerr << e.what() << ", " << e.displayText() << std::endl; |
82 | throw; |
83 | } |
84 | |
85 | |