How to use jq to transform array of objects into separated list of key values

This is related to my previous question: How to use jq to format array of objects to separated list of key values

How can I (generically) transform the input file below to the output file below, using jq. The value at key "id" uniqely identifies the array element. The record format of the output file is: (value at key "id") | key | value.

I can do this if I add awk to solution of previous question, but I am having trouble getting my head around doing it all in jq.

Input file:

[{"id": 11, "b": 100},
 {"id": 12, "d": "fred", "e": 300}]

Output File:

11|id|11
11|b|100
12|id|12
12|d|fred
12|e|300

CodePudding user response：

Here's a solution using to_entries, which decomposes an object into an array of key-value pairs:

jq -r '.[] | .id as $id | to_entries[] | [$id,.key,.value] | join("|")'

11|id|11
11|b|100
12|id|12
12|d|fred
12|e|300