Re: When using the Quickbase JSON API is there a way to add a new created relationship field to the form similar to when creating a normal field?

It's a two-step process per field.

First, use this endpoint to add the new field:

https://helpv2.quickbase.com/hc/en-us/articles/4418302265236-API-AddField

At minimum, you'll want to pass mode, type, and add_to_forms. Type must match the field type of the intended lookup field in the parent table.

Also, make sure your legacy form is set to "Auto-add new fields". (I have no idea what will happen with the new form styles.)

<mode>lookup</mode>
<type>text</mode> // must match intended lookup field!
<add_to_forms>1</add_to_forms>

Second, use this endpoint to update the the lutfid and lusfid attributes of the newly created field:

https://helpv2.quickbase.com/hc/en-us/articles/4418310972052-API-SetFieldProperties

<lutfid>8</lutfid> // the field ID of the reference field in the same table
<lusfid>6</lusfid> // the field ID of the source field in the lookup table

lutfid and lusfid are not in the XML API documentation, but they are visible when you call API_GetFieldProperties on a lookup field. For some reason, they are ignored when passed to API_AddField, but they are accepted when passed to API_SetFieldProperties.

I tested this out and it all works: the field is created, it's a lookup, and it appears by default on the legacy form. 

IMO, this method is going to require a lot of overhead to script/automate. If I were in your shoes and this was a one-time operation, I would consider using the JSON API to create the fields (very easy) and manually add them to the form (painfully monotonous). 

Good luck!

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gary
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