Filter keys with specific JSON values in JSON-LD files

Question

I have a zip file(GZ) which when unzipped contains JSON in each line. Below is one sample JSON line. I am trying to extract specific fields only to CSV file using jq. I want to extract these fields with a condition that the type key should have the value dissertation only.

{
  "id": "https://openalex.org/W2777209504",
  "doi": "https://doi.org/10.24026/1818-1384.1(42).2013.77470",
  "display_name": "Hyperandrogenism as a factor of reproductive losses",
  "title": "Hyperandrogenism as a factor of reproductive losses",
  "publication_year": 2013, 
  "publication_date": "2013-03-27",
  "ids": {
    "openalex": "https://openalex.org/W2777209504",
    "doi": "https://doi.org/10.24026/1818-1384.1(42).2013.77470",
    "mag": 2777209504
  },
  "type": "journal-article",
  "counts_by_year": [
    {
      "year": 2019,
      "cited_by_count": 1
    }
  ],
  "cited_by_api_url": "https://api.openalex.org/works?filter=cites:W2777209504",
  "updated_date": "2021-11-03",
  "created_date": "2018-01-05",
  "abstract_inverted_index": {}
}

I tried the below two commands and neither of them worked: \

1. gzcat -c sample.gz | jq -rc '[.doi,.title, .publication_year, .publication_date, .type] | select(.type |contains("dissertation")) | @csv'>target.csv
2. gzcat -c sample.gz | jq -rc '[.doi,.title, .publication_year, .publication_date, .type] | select(.type=="dissertation") | @csv'>target.csv

The output received for both of them is:
jq: error (at <stdin>:108753): Cannot index string with string "title"

I tried all possibles ways to filter down my JSON-LD file but I am unable to succeed. Any pointers will be of great help.

Answer 1

In both your attempts, the select is incorrectly formulated (or in the wrong place, depending on your point of view). This would work:

select(.type == "dissertation")
| [.doi,.title, .publication_year, .publication_date, .type]
| @csv