1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
#include <DataTypes/DataTypeDateTime.h>
#include <Functions/IFunction.h>
#include <Core/DecimalFunctions.h>
#include <Functions/FunctionFactory.h>
#include <Core/Field.h>
namespace DB
{
namespace ErrorCodes
{
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
}
namespace
{
/// Get the UTC time. (It is a constant, it is evaluated once for the entire query.)
class ExecutableFunctionUTCTimestamp : public IExecutableFunction
{
public:
explicit ExecutableFunctionUTCTimestamp(time_t time_) : time_value(time_) {}
String getName() const override { return "UTCTimestamp"; }
ColumnPtr executeImpl(const ColumnsWithTypeAndName &, const DataTypePtr &, size_t input_rows_count) const override
{
return DataTypeDateTime().createColumnConst(
input_rows_count,
static_cast<UInt64>(time_value));
}
private:
time_t time_value;
};
class FunctionBaseUTCTimestamp : public IFunctionBase
{
public:
explicit FunctionBaseUTCTimestamp(time_t time_, DataTypes argument_types_, DataTypePtr return_type_)
: time_value(time_), argument_types(std::move(argument_types_)), return_type(std::move(return_type_)) {}
String getName() const override { return "UTCTimestamp"; }
const DataTypes & getArgumentTypes() const override
{
return argument_types;
}
const DataTypePtr & getResultType() const override
{
return return_type;
}
ExecutableFunctionPtr prepare(const ColumnsWithTypeAndName &) const override
{
return std::make_unique<ExecutableFunctionUTCTimestamp>(time_value);
}
bool isDeterministic() const override { return false; }
bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return false; }
private:
time_t time_value;
DataTypes argument_types;
DataTypePtr return_type;
};
class UTCTimestampOverloadResolver : public IFunctionOverloadResolver
{
public:
static constexpr auto name = "UTCTimestamp";
String getName() const override { return name; }
bool isDeterministic() const override { return false; }
bool isVariadic() const override { return false; }
size_t getNumberOfArguments() const override { return 0; }
static FunctionOverloadResolverPtr create(ContextPtr) { return std::make_unique<UTCTimestampOverloadResolver>(); }
DataTypePtr getReturnTypeImpl(const ColumnsWithTypeAndName & arguments) const override
{
if (!arguments.empty())
{
throw Exception(ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH, "Arguments size of function {} should be 0", getName());
}
return std::make_shared<DataTypeDateTime>();
}
FunctionBasePtr buildImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &) const override
{
if (!arguments.empty())
{
throw Exception(ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH, "Arguments size of function {} should be 0", getName());
}
return std::make_unique<FunctionBaseUTCTimestamp>(time(nullptr), DataTypes(), std::make_shared<DataTypeDateTime>("UTC"));
}
};
}
/// UTC_timestamp for MySQL interface support
REGISTER_FUNCTION(UTCTimestamp)
{
factory.registerFunction<UTCTimestampOverloadResolver>(FunctionDocumentation{
.description=R"(
Returns the current date and time at the moment of query analysis. The function is a constant expression.
Same as `now('UTC')`. Was added only for MySQL support. `now` is preferred.
Example:
[example:typical]
)",
.examples{
{"typical", "SELECT UTCTimestamp();", ""}},
.categories{"Dates and Times"}}, FunctionFactory::CaseInsensitive);
factory.registerAlias("UTC_timestamp", UTCTimestampOverloadResolver::name, FunctionFactory::CaseInsensitive);
}
}
|
