
使用此转换可根据输入数据生成直方图,从而直观显示数值的分布情况。其中的选项:
Bucket size - 桶中最低和最高项目之间的范围(xMin 到 xMax)。
Bucket offset - 非零数据桶的偏移量。
Combine series - 使用所有可用序列创建统一的直方图。
假如存在如下原始数据:
系列1(查询A):
| A | B | C | 
| 1 | 3 | 5 | 
| 2 | 4 | 6 | 
| 3 | 5 | 7 | 
| 4 | 6 | 8 | 
| 5 | 7 | 9 | 
上述表格对应数据的 SQL 语句如下:
select 1 as A, 3 as B, 5 as C from dual union all select 2 as A, 4 as B, 6 as C from dual union all select 3 as A, 5 as B, 7 as C from dual union all select 4 as A, 6 as B, 8 as C from dual union all select 5 as A, 7 as B, 9 as C from dual
将上述 SQL 语句作为 Grafana 图表的数据,如下图:

系列2(查询B):
| C | 
| 5 | 
| 6 | 
| 7 | 
| 8 | 
| 9 | 
上述数据对应的 SQL 语句如下:
select 5 as C from dual union all select 6 as C from dual union all select 7 as C from dual union all select 8 as C from dual union all select 9 as C from dual
将上述 SQL 语句作为 Grafana 图表的数据,如下图:

创建一个类型为“Histogram”的数据转换,转换后的数据如下图:

如果我们将“Bucket size”设置为 4,“Combine series”设置为选中,效果如下图:

使用生成的直方图直观显示数值的分布情况,深入了解数据的分布和密度。
