1 | #include <DataTypes/DataTypeDateTime.h> |
---|---|
2 | #include <DataTypes/DataTypeDateTime64.h> |
3 | |
4 | #include <Core/Field.h> |
5 | |
6 | #include <Functions/IFunctionImpl.h> |
7 | #include <Functions/FunctionFactory.h> |
8 | #include <Functions/extractTimeZoneFromFunctionArguments.h> |
9 | |
10 | #include <IO/WriteHelpers.h> |
11 | #include <Common/assert_cast.h> |
12 | |
13 | |
14 | namespace DB |
15 | { |
16 | |
17 | namespace ErrorCodes |
18 | { |
19 | extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH; |
20 | extern const int ILLEGAL_TYPE_OF_ARGUMENT; |
21 | } |
22 | |
23 | /// Just changes time zone information for data type. The calculation is free. |
24 | class FunctionToTimeZone : public IFunction |
25 | { |
26 | public: |
27 | static constexpr auto name = "toTimeZone"; |
28 | static FunctionPtr create(const Context &) { return std::make_shared<FunctionToTimeZone>(); } |
29 | |
30 | String getName() const override |
31 | { |
32 | return name; |
33 | } |
34 | |
35 | size_t getNumberOfArguments() const override { return 2; } |
36 | |
37 | DataTypePtr getReturnTypeImpl(const ColumnsWithTypeAndName & arguments) const override |
38 | { |
39 | if (arguments.size() != 2) |
40 | throw Exception("Number of arguments for function "+ getName() + " doesn't match: passed " |
41 | + toString(arguments.size()) + ", should be 2", |
42 | ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH); |
43 | |
44 | const auto which_type = WhichDataType(arguments[0].type); |
45 | if (!which_type.isDateTime() && !which_type.isDateTime64()) |
46 | throw Exception{"Illegal type "+ arguments[0].type->getName() + " of argument of function "+ getName() + |
47 | ". Should be DateTime or DateTime64", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT}; |
48 | |
49 | String time_zone_name = extractTimeZoneNameFromFunctionArguments(arguments, 1, 0); |
50 | if (which_type.isDateTime()) |
51 | return std::make_shared<DataTypeDateTime>(time_zone_name); |
52 | |
53 | const auto * date_time64 = assert_cast<const DataTypeDateTime64 *>(arguments[0].type.get()); |
54 | return std::make_shared<DataTypeDateTime64>(date_time64->getScale(), time_zone_name); |
55 | } |
56 | |
57 | void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t /*input_rows_count*/) override |
58 | { |
59 | block.getByPosition(result).column = block.getByPosition(arguments[0]).column; |
60 | } |
61 | }; |
62 | |
63 | void registerFunctionToTimeZone(FunctionFactory & factory) |
64 | { |
65 | factory.registerFunction<FunctionToTimeZone>(); |
66 | } |
67 | |
68 | } |
69 |