1#include <Functions/IFunctionImpl.h>
2#include <Functions/GatherUtils/GatherUtils.h>
3#include <DataTypes/DataTypeArray.h>
4#include <DataTypes/getLeastSupertype.h>
5#include <Columns/ColumnArray.h>
6#include <Columns/ColumnConst.h>
7#include <Interpreters/castColumn.h>
8#include <Common/typeid_cast.h>
9
10
11namespace DB
12{
13
14namespace ErrorCodes
15{
16 extern const int LOGICAL_ERROR;
17 extern const int ILLEGAL_TYPE_OF_ARGUMENT;
18}
19
20
21class FunctionArrayPush : public IFunction
22{
23public:
24 FunctionArrayPush(const Context & context_, bool push_front_, const char * name_)
25 : context(context_), push_front(push_front_), name(name_) {}
26
27 String getName() const override { return name; }
28
29 bool isVariadic() const override { return false; }
30 size_t getNumberOfArguments() const override { return 2; }
31
32 DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
33 {
34 if (arguments[0]->onlyNull())
35 return arguments[0];
36
37 auto array_type = typeid_cast<const DataTypeArray *>(arguments[0].get());
38 if (!array_type)
39 throw Exception("First argument for function " + getName() + " must be an array but it has type "
40 + arguments[0]->getName() + ".", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
41
42 auto nested_type = array_type->getNestedType();
43
44 DataTypes types = {nested_type, arguments[1]};
45
46 return std::make_shared<DataTypeArray>(getLeastSupertype(types));
47 }
48
49 void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t input_rows_count) override
50 {
51 const auto & return_type = block.getByPosition(result).type;
52
53 if (return_type->onlyNull())
54 {
55 block.getByPosition(result).column = return_type->createColumnConstWithDefaultValue(input_rows_count);
56 return;
57 }
58
59 auto result_column = return_type->createColumn();
60
61 auto array_column = block.getByPosition(arguments[0]).column;
62 auto appended_column = block.getByPosition(arguments[1]).column;
63
64 if (!block.getByPosition(arguments[0]).type->equals(*return_type))
65 array_column = castColumn(block.getByPosition(arguments[0]), return_type, context);
66
67 const DataTypePtr & return_nested_type = typeid_cast<const DataTypeArray &>(*return_type).getNestedType();
68 if (!block.getByPosition(arguments[1]).type->equals(*return_nested_type))
69 appended_column = castColumn(block.getByPosition(arguments[1]), return_nested_type, context);
70
71 std::unique_ptr<GatherUtils::IArraySource> array_source;
72 std::unique_ptr<GatherUtils::IValueSource> value_source;
73
74 size_t size = array_column->size();
75 bool is_const = false;
76
77 if (auto const_array_column = typeid_cast<const ColumnConst *>(array_column.get()))
78 {
79 is_const = true;
80 array_column = const_array_column->getDataColumnPtr();
81 }
82
83 if (auto argument_column_array = typeid_cast<const ColumnArray *>(array_column.get()))
84 array_source = GatherUtils::createArraySource(*argument_column_array, is_const, size);
85 else
86 throw Exception{"First arguments for function " + getName() + " must be array.", ErrorCodes::LOGICAL_ERROR};
87
88
89 bool is_appended_const = false;
90 if (auto const_appended_column = typeid_cast<const ColumnConst *>(appended_column.get()))
91 {
92 is_appended_const = true;
93 appended_column = const_appended_column->getDataColumnPtr();
94 }
95
96 value_source = GatherUtils::createValueSource(*appended_column, is_appended_const, size);
97
98 auto sink = GatherUtils::createArraySink(typeid_cast<ColumnArray &>(*result_column), size);
99
100 GatherUtils::push(*array_source, *value_source, *sink, push_front);
101
102 block.getByPosition(result).column = std::move(result_column);
103 }
104
105 bool useDefaultImplementationForConstants() const override { return true; }
106 bool useDefaultImplementationForNulls() const override { return false; }
107
108private:
109 const Context & context;
110 bool push_front;
111 const char * name;
112};
113
114}
115