Does Time series data format support non-number data type?

#1

Dear,

I’m trying to write a Custom Datasource plugin for Grafana.
The problem is that other than number my data source also contains string data.
So if I format the time series data as below. It does not display on Graph.

[
  {
    "target":"upper_75",
    "datapoints":[
      [622, 1450754160000],
      [365, 1450754220000]
    ]
  },
  {
    "target":"upper_65",
    "datapoints":[
      ['a', 1450754160000],
      ['b', 1450754220000]
    ]
  }
]

I can filter out the string data.
However, I wonder if it Grafana support string data type?
Please help.
I’m using Grafana v5.4.0 (69c5191)

Thank you,