blob: 3a648f00eba547bdf9e36fcc43c2747b84e0a474 (
plain) (
blame)
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
|
#pragma once
#include <Formats/FormatFactory.h>
#include <Processors/Formats/IOutputFormat.h>
#include <string>
namespace DB
{
class WriteBuffer;
/** Output format that writes data row by row.
*/
class IRowOutputFormat : public IOutputFormat
{
public:
/// Used to work with IRowOutputFormat explicitly.
void writeRow(const Columns & columns, size_t row_num)
{
first_row = false;
write(columns, row_num);
}
virtual void writeRowBetweenDelimiter() {} /// delimiter between rows
protected:
IRowOutputFormat(const Block & header, WriteBuffer & out_);
void consume(Chunk chunk) override;
void consumeTotals(Chunk chunk) override;
void consumeExtremes(Chunk chunk) override;
virtual bool supportTotals() const { return false; }
virtual bool supportExtremes() const { return false; }
/** Write a row.
* Default implementation calls methods to write single values and delimiters
* (except delimiter between rows (writeRowBetweenDelimiter())).
*/
virtual void write(const Columns & columns, size_t row_num);
virtual void writeMinExtreme(const Columns & columns, size_t row_num);
virtual void writeMaxExtreme(const Columns & columns, size_t row_num);
virtual void writeTotals(const Columns & columns, size_t row_num);
/** Write single value. */
virtual void writeField(const IColumn & column, const ISerialization & serialization, size_t row_num) = 0;
/** Write delimiter. */
virtual void writeFieldDelimiter() {} /// delimiter between values
virtual void writeRowStartDelimiter() {} /// delimiter before each row
virtual void writeRowEndDelimiter() {} /// delimiter after each row
virtual void writePrefix() override {} /// delimiter before resultset
virtual void writeSuffix() override {} /// delimiter after resultset
virtual void writeBeforeTotals() {}
virtual void writeAfterTotals() {}
virtual void writeBeforeExtremes() {}
virtual void writeAfterExtremes() {}
virtual void finalizeImpl() override {} /// Write something after resultset, totals end extremes.
bool haveWrittenData() { return !first_row || getRowsReadBefore() != 0; }
size_t num_columns;
DataTypes types;
Serializations serializations;
bool first_row = true;
};
}
|
