1 | #include <Interpreters/addMissingDefaults.h> |
2 | |
3 | #include <Common/typeid_cast.h> |
4 | #include <DataTypes/NestedUtils.h> |
5 | #include <DataTypes/DataTypeArray.h> |
6 | #include <Columns/ColumnArray.h> |
7 | #include <Interpreters/evaluateMissingDefaults.h> |
8 | #include <Core/Block.h> |
9 | #include <Storages/ColumnDefault.h> |
10 | |
11 | |
12 | namespace DB |
13 | { |
14 | |
15 | Block addMissingDefaults(const Block & block, |
16 | const NamesAndTypesList & required_columns, |
17 | const ColumnDefaults & column_defaults, |
18 | const Context & context) |
19 | { |
20 | /// For missing columns of nested structure, you need to create not a column of empty arrays, but a column of arrays of correct lengths. |
21 | /// First, remember the offset columns for all arrays in the block. |
22 | std::map<String, ColumnPtr> offset_columns; |
23 | |
24 | for (size_t i = 0, size = block.columns(); i < size; ++i) |
25 | { |
26 | const auto & elem = block.getByPosition(i); |
27 | |
28 | if (const ColumnArray * array = typeid_cast<const ColumnArray *>(&*elem.column)) |
29 | { |
30 | String offsets_name = Nested::extractTableName(elem.name); |
31 | auto & offsets_column = offset_columns[offsets_name]; |
32 | |
33 | /// If for some reason there are different offset columns for one nested structure, then we take nonempty. |
34 | if (!offsets_column || offsets_column->empty()) |
35 | offsets_column = array->getOffsetsPtr(); |
36 | } |
37 | } |
38 | |
39 | const size_t rows = block.rows(); |
40 | Block res; |
41 | |
42 | /// We take given columns from input block and missed columns without default value |
43 | /// (default and materialized will be computed later). |
44 | for (const auto & column : required_columns) |
45 | { |
46 | if (block.has(column.name)) |
47 | { |
48 | res.insert(block.getByName(column.name)); |
49 | continue; |
50 | } |
51 | |
52 | if (column_defaults.count(column.name)) |
53 | continue; |
54 | |
55 | String offsets_name = Nested::extractTableName(column.name); |
56 | if (offset_columns.count(offsets_name)) |
57 | { |
58 | ColumnPtr offsets_column = offset_columns[offsets_name]; |
59 | DataTypePtr nested_type = typeid_cast<const DataTypeArray &>(*column.type).getNestedType(); |
60 | UInt64 nested_rows = rows ? get<UInt64>((*offsets_column)[rows - 1]) : 0; |
61 | |
62 | ColumnPtr nested_column = nested_type->createColumnConstWithDefaultValue(nested_rows)->convertToFullColumnIfConst(); |
63 | auto new_column = ColumnArray::create(nested_column, offsets_column); |
64 | res.insert(ColumnWithTypeAndName(std::move(new_column), column.type, column.name)); |
65 | continue; |
66 | } |
67 | |
68 | /** It is necessary to turn a constant column into a full column, since in part of blocks (from other parts), |
69 | * it can be full (or the interpreter may decide that it is constant everywhere). |
70 | */ |
71 | auto new_column = column.type->createColumnConstWithDefaultValue(rows)->convertToFullColumnIfConst(); |
72 | res.insert(ColumnWithTypeAndName(std::move(new_column), column.type, column.name)); |
73 | } |
74 | |
75 | /// Computes explicitly specified values (in column_defaults) by default and materialized columns. |
76 | evaluateMissingDefaults(res, required_columns, column_defaults, context); |
77 | return res; |
78 | } |
79 | |
80 | } |
81 | |