1 | #pragma once |
2 | |
3 | #include <string> |
4 | #include <Processors/Formats/IOutputFormat.h> |
5 | #include <Formats/FormatSettings.h> |
6 | #include <Core/Block.h> |
7 | |
8 | |
9 | namespace DB |
10 | { |
11 | |
12 | class WriteBuffer; |
13 | |
14 | |
15 | /** A data format designed to simplify the implementation of the ODBC driver. |
16 | * ODBC driver is designed to be build for different platforms without dependencies from the main code, |
17 | * so the format is made that way so that it can be as easy as possible to parse it. |
18 | * A header is displayed with the required information. |
19 | * The data is then output in the order of the rows. Each value is displayed as follows: length in VarUInt format, then data in text form. |
20 | */ |
21 | class ODBCDriverBlockOutputFormat : public IOutputFormat |
22 | { |
23 | public: |
24 | ODBCDriverBlockOutputFormat(WriteBuffer & out_, const Block & , const FormatSettings & format_settings_); |
25 | |
26 | String getName() const override { return "ODBCDriverBlockOutputFormat" ; } |
27 | |
28 | void consume(Chunk) override; |
29 | void finalize() override; |
30 | |
31 | std::string getContentType() const override { return "application/octet-stream" ; } |
32 | |
33 | private: |
34 | const FormatSettings format_settings; |
35 | bool prefix_written = false; |
36 | |
37 | void writePrefixIfNot() |
38 | { |
39 | if (!prefix_written) |
40 | writePrefix(); |
41 | |
42 | prefix_written = true; |
43 | } |
44 | |
45 | void writePrefix(); |
46 | }; |
47 | |
48 | } |
49 | |