Repeats within repeats

[FrankHerbert]

I'm creating a form that will allow field workers to record individual tree heights within a number of plots, within a number of areas.

1. The field worker will visit an area and record general information (date, objectives, weather etc.).

2. They then visit a number plots within the area and record more plot-specific info (plot ID, slope, aspect etc.)

3. In each plot the field worker records individual trees heights

Currently the only way I know how to implement this is via table joins leveraged on parent Global IDs populating the GUID field in the child.

Area Survey (parent)

Plot Survey (Area Survey Global ID -> GUID)

Tree Survey (Plot Survey Global ID -> GUID)

The end goal is to have several 'Area Surveys' containing 50+ plots that each contain basic information on tree heights.

I'm looking for some general advice to make sure I'm on the right track. Alternatively, if there is a better/more efficient way of doing this then I would like to learn about it.

Thanks in advance

[DougBrowning · Accepted solution]

123 will take care of all the Ids for you in repeats.  It has a parentglobalid field in each child and it will populate for you.

That said I like to control the ids myself by passing them down to the repeats in fields.  GlobalIds fall apart if you have to say export from AGOL into SDE.  

At the top level of the form I have say SiteID.  Then I add a field like PlotSiteID that holds the SiteID in the plot.  Then a TreeSiteID that inherits that.  I use a second set of relationship classes for these but that is up to you.

See here https://doc.arcgis.com/en/survey123/desktop/create-surveys/xlsformrepeats.htm 

More details on my method https://community.esri.com/t5/arcgis-survey123-questions/mapping-with-survey123-within-a-polygon-or-...

And why I don't use GlobalIDs https://community.esri.com/t5/arcgis-collector-questions/related-tables-for-offline-data-collection/... 

Hope that helps

[FrankHerbert]

Hi @DougBrowning ,

Thank you for your help. Currently we don't anticipate the need to export from AGOL to SDE or FGDB but I will have a play around with using custom unique IDs as well as/instead of the Global IDs. I read your comments in the links and there is some interesting points.

I forgot to mention, I have created the Survey123 form based on existing feature layers and relationship classes. So far the draft workflow I created seems to working OK, but I hope it holds up when large volumes of data start coming in. I'm also interested in using values from indexed repeats that may strengthen the workflow.

Thanks again for your feedback.