1 | #pragma once |
2 | |
3 | #include <DataStreams/IBlockInputStream.h> |
4 | #include <Storages/ColumnDefault.h> |
5 | |
6 | |
7 | namespace DB |
8 | { |
9 | |
10 | |
11 | /** This stream adds three types of columns into block |
12 | * 1. Columns, that are missed inside request, but present in table without defaults (missed columns) |
13 | * 2. Columns, that are missed inside request, but present in table with defaults (columns with default values) |
14 | * 3. Columns that materialized from other columns (materialized columns) |
15 | * All three types of columns are materialized (not constants). |
16 | */ |
17 | class AddingMissedBlockInputStream : public IBlockInputStream |
18 | { |
19 | public: |
20 | AddingMissedBlockInputStream( |
21 | const BlockInputStreamPtr & input_, |
22 | const Block & , |
23 | const ColumnDefaults & column_defaults_, |
24 | const Context & context_); |
25 | |
26 | String getName() const override { return "AddingMissed" ; } |
27 | Block () const override { return header; } |
28 | |
29 | private: |
30 | Block readImpl() override; |
31 | |
32 | BlockInputStreamPtr input; |
33 | /// Blocks after this stream should have this structure |
34 | const Block ; |
35 | const ColumnDefaults column_defaults; |
36 | const Context & context; |
37 | }; |
38 | |
39 | |
40 | } |
41 | |