使用 jq 获取 json 的每个唯一键的值列表

Question

guys. There's the task: to get all unique keys and lists of matching values for these keys and then wrap them in {}

The json looks like:

{
    "sepalLength": 5,
    "sepalWidth": 3.3,
    "petalLength": 1.4,
    "petalWidth": 0.2,
    "species": "setosa"
  },
  {
    "sepalLength": 7,
    "sepalWidth": 3.2,
    "petalLength": 4.7,
    "petalWidth": 1.4,
    "species": "versicolor"
  },
  {
    "sepalLength": 6.4,
    "sepalWidth": 3.2,
    "petalLength": 4.5,
    "petalWidth": 1.5,
    "species": "versicolor"
  },
...

And the result must look this way:

{
    "species": ["setosa", "setosa", ...],
    "petalWidth": [1.2, ...],
    ...
}

Answer 1

Assuming, your input data is an array

[
  {
    "sepalLength": 5,
    "sepalWidth": 3.3,
    "petalLength": 1.4,
    "petalWidth": 0.2,
    "species": "setosa"
  },
  {
    "sepalLength": 7,
    "sepalWidth": 3.2,
    "petalLength": 4.7,
    "petalWidth": 1.4,
    "species": "versicolor"
  },
  ...
]

The following

jq '[(map(keys[]) | unique[]) as $key | {($key): map(.[$key])} ] | add'

if fed with your sample data will produce something like

{
  "petalLength": [1.4,4.7,4.5],
  "petalWidth": [0.2,1.4,1.5],
  "sepalLength": [5,7,6.4],
  "sepalWidth": [3.3,3.2,3.2],
  "species": ["setosa","versicolor","versicolor"]
}