You can use jq '.[] | .login, .id' to obtain each login followed by its id.

Use @tsv to generated tab-separated values as output:

Copyjq -r '[.user, .cmd] | @tsv' <yourfile

...emits, given your input file:

Copyalex    echo '123'
john    echo '456'
alex    echo '789'

...though if you're filtering for only your user account, you can just print cmd directly, since the user value is known:

Copyjq -r 'select(.user == "alex") | .cmd' 

Here is an approach using some sample code and data from my answer to a similar question on Stack Overflow.

To choose multiple fields you can use Object Construction. E.g this filter makes an object containing just PublicDnsName and VpcId from each instance:

  .Reservations[]
| .Instances[]
| {PublicDnsName, VpcId}

If this filter is in filter.jq and the sample data from that other answer is in data.json then running

$ jq -M -f filter.jq data.json

produces

{
  "PublicDnsName": "xxxxxxxx",
  "VpcId": "vpc-eb09eb8e"
}

Once you have objects containing what you want getting the data into another format (e.g. csv) is easy. With this filter

  .Reservations[]
| .Instances[]
| {PublicDnsName, VpcId}
| [.[]]
| @csv

and the -r option

$ jq -M -r -f filter.jq data.json

jq produces

"xxxxxxxx","vpc-eb09eb8e"

To add a filtering condition, e.g. VpcId is not null, add a select.

  .Reservations[]
| .Instances[]
| {PublicDnsName, VpcId}
| select(.VpcId != null)
| [.[]]
| @csv

Use the "join", -j

$ jq -jr '.[]|"name:", " ",.name, "\n","groups:", (.grp[]|" ",.name),"\n"' test_json
name: cust1
groups: BA2 GA1 NA1 TR3 TS1

And with a place holder

$ jq -jr '.[]|"name:", " ",.name, "\n","groups:", (.grp//[{"name":"-"}]|.[]|" ",.name),"\n"' test_json
name: cust1
groups: -

Sorry didn't see all the attention here, @tony-sol you can do it like this:

yq '.[] |= pick(["name", "status"])' data1.yaml

Explanation:

• You want to pick particular fields from each map in the array
• .[] |= will match each element in the array, and update that element w.r.t itself
• pick([]) will take a given map and pick fields (omitting the rest)

See https://mikefarah.gitbook.io/yq/operators/pick for details.

The different with doing .[] | (.name, .status) is that will match all elements and just pulling out just those values.

While it is probably best to use a tool like the one peak suggested if your json isn't too complex you could use a second jq invocation to postprocess the output of the first. For example if your data is in data.json

$ jq -M . data.json | jq -MRsr 'gsub("\n      +";"")|gsub("\n    ]";"]")'

produces

{
  "frameGrid": {
    "size": [24,24],
    "dimensions": [1,1],
    "names": [["default"]]
  }
}

The easiest way in your example is to use String Interpolation along with the -r option. e.g.

echo '{ "fmep": { "foo": 112, "bar": 234324, "cat": 21343423 } }' | \
jq -r '.fmep| "\(.foo) \(.bar)"'

produces

112 234324

You may also want to consider putting the values in an array and using @tsv e.g.

echo '{ "fmep": { "foo": 112, "bar": 234324, "cat": 21343423 } }' | \
jq -r '.fmep | [.foo, .bar] | @tsv'

which produces tab-separated

112 234324