PQ docs_id to be expression

[githubmanticore]

it might be better to set doc_id as json.field (j.gid as doc_id) or even arbitrary expression (attr.a[5].id as doc_id)

It also worth to evaluate this expression only for docs at result set unlike what is done now at statement parsing time.

[githubmanticore]

➤ Stan commented:

that allows to use all data as JSON PQ queries as

call pq('pq_idx', '{"json": 
{ 
  "id": 18, 
  "text": { 
    "type": "status", 
    "event": "add", 
    "status": { 
      "isLongText": false 
    } 
  } 
}}', 1 as query, 'json.id' as docs_id, 1 as docs_json, 1 as docs); 

[githubmanticore]

➤ Gloria Vinogradova commented:

PQ project is expired for now. Does the issue is worth for development still?

[githubmanticore]

➤ Sergey Nikolaev commented:

The task makes sense, but is not actual at the moment. Let's keep it open for future.