What high-level problem are you trying to solve?
Dynamically linking data across forms in near real-time.
Short Version
We want to be able to automatically check and update forms in ODK Collect using shorter-than 15 minute intervals. Right now the intervals are 15 minutes, 1 hour, 6 hours, and 24 hours. But a 1-minute interval would allow users to collect data about the same entity using different forms, linked by a common ID, with less lag.
Use Case 1 - Registration Data
Consider a health post that has an intake form which captures only very basic information (name, age, etc.). It generates a patient or case ID number, ${case_id}, which will link this case across everything that happens afterward.
Once a patient sees a nurse, the nurse fills a form describing the patient's complaints, etc. In that form, we use "select_one case_id" to select from case IDs that have been generated via the form.
With automatic form updates in ODK Collect, this works very nicely. But the fastest automatic updates check every 15 minutes, and it would be helpful if there were a faster option (i.e. every minute).
Use Case 2 - One HH, Multiple Respondents
Consider a HH survey that seeks information from a male and female adult. Interviews need to be conducted by enumerators of the same sex as the respondent; data needs to be linked between the male and female respondents and broader household questions.
We always avoid having respondents enter unique IDs -- that will later be used to link responses from two datasets -- manually, because errors are too high and difficult to resolve. So in this use we could have a household introduction survey with a household roster. Once submitted, that form generates a Household ID, linked to the name of the head of household.
Now, when the female enumerator selects the female respondent to interview, they can select from a menu of household IDs, which will link her response to the household. They can also select, within a household, her roster/member ID, to link her to information captured about her during the household roster.
Broader Usage
Both these use cases work off-the-shelf with Ona, which allows linking a dataset (updated dynamically) to a form. But the 15-minute lag is problematic.
This revision would benefit non-Ona users also -- allowing the same dynamic linking for any user if they are able to download data from one form and update the .csv attached to secondary forms via API.
Any ideas on how ODK could help you solve it?
Allow users to opt in to automatic form updates using a more frequent interval (1 minute).
Upload any helpful links, sketches, and videos.
This seems related to discussions and implementation of entity-based data collection here. However, I think it is a simpler solution for some specific use cases and users, and (I think) would work without an ODK server. From the little I've read on entity-based data in ODK, it requires a backend approval/review of the data, which is comparatively labor-intensive and also slows down the ability to use the Follow-Up Form.
Make sure you have updated the form before starting". You can also put household selection as the first question so that the data collector can immediately verify whether they have access to the household they need before getting far into the survey. If they don't see the household they need, they can exit the form and refresh.