Can you avoid overwriting fields when values are NULL/blank?

[Megan_Koelemay]

Is there a way avoid overwriting data when a form is submitted with blank/null values? 

We use a single webform in several different places on our website, and the form fields differ depending on which form the user is filling out, so we hide unused fields.  When the user submits the form, the hidden fields get submitted too, and any existing data on them is wiped out. 

We can't use Marketo's built-in feature to block field updates, because it's not possible to use it to block ONLY the null/blank values.  It retains the original value for the lifetime of the field, which is not our goal.

https://docs.marketo.com/display/public/DOCS/Block+Updates+to+a+Field

[SanfordWhiteman]

Something's wrong with your testing. Empty strings don't overwrite filled values.

[SanfordWhiteman]

See https://blog.teknkl.com/clearing-lead-fields-when-no-value-submitted/

[Megan_Koelemay]

What about through activity logs vs. lead fields?  We're pulling data from form fills into our CRM via the activity table, not the lead table (I might be using the wrong terminology as I'm not a dev, but that's my basic understanding).  

[SanfordWhiteman]

What about through activity logs vs. lead fields?  We're pulling data from form fills into our CRM via the activity table, not the lead table (I might be using the wrong terminology as I'm not a dev, but that's my basic understanding).  

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Pulling data from the point-in-time Filled Out Form activity doesn't make sense unless you care only about that specific action and not any further results of that action.

The Filled Out Form activity doesn't represent the data actually saved to the lead, because [a] blocked fields will not be overwritten and [b] as noted above, blank form values will not end up blanking out the fields on the lead.  

Furthermore, the FoF detail can include fields that aren't even in Marketo (due to JS-side misconfiguration, for example)! 

There is no way to tell from a Filled Out Form detail what the lead looks like.