dsq failed to recognize nested field, if its parent object absents in some records

[mon-jai]

Describe the bug and expected behavior

dsq failed to recognize nested field if its parent object absents in some records.

Reproduction steps

dsq failed to retrieve location.city, if location is absent in some records.

user_addresses.json

[
  {"name": "Agarrah", "location": {"city": "Toronto", "address": { "number": 1002 }}},
  {"name": "Minoara", "location": {"city": "Mexico City", "address": { "number": 19 }}},
  {"name": "Fontoon"}
]

Result:

dsq user_addresses.json 'SELECT name, "location.city" FROM {}'
[{"name":"Agarrah","\"location.city\"":"location.city"},
{"name":"Minoara","\"location.city\"":"location.city"},
{"name":"Fontoon","\"location.city\"":"location.city"}]

Expected behavior:

dsq user_addresses.json 'SELECT name, "location.city" FROM {}'
[{"name":"Agarrah","location.city":"Toronto"},
{"name":"Minoara","location.city":"Mexico City"},
{"name":"Fontoon","location.city":null}]

Versions

• OS: Linux DESKTOP-IID1F0E 5.15.90.1-microsoft-standard-WSL2 #1 SMP Fri Jan 27 02:56:13 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
• Shell: Bash
• dsq version: 0.23.0

[eatonphil]

Here's a way you can work around this:

$ dsq user_addresses.json 'select location->>"address" FROM {}'
[{"location->>\"address\"":"{\"number\":1002}"},
{"location->>\"address\"":"{\"number\":19}"},
{"location->>\"address\"":null}]

[mon-jai]

@eatonphil That is great. But it won't work if every record contains the location field, so won't work consistently on other datasets with the same schema.

Maybe we can add a flag to also include the string representation of objects, regardless of whether or not it can be extracted to sub-fields, like something called --preserve-json-string?

# location field will present in all situations
$ dsq user_addresses.json 'select location->>"address" FROM {}' --preserve-json-string

[eatonphil]

But it won't work if every record contains the location field, so won't work consistently on other datasets with the same schema.

I don't understand what you mean by this?