If you have a Wordpress ID field, you can use the Rest API to designate this as your lookUpfield for updates. However, you will first need to populate this field into Marketo, before you can use it as a key, otherwise it can potentially generate duplicates: http://developers.marketo.com/documentation/rest/createupdate-leads/
Not having all the details, here are some quick thoughts:
Do you collect the email address currently in WP or no?
If you do collect the email
In Marketo, you could store the Wordpress Id in a custom field and contact support to setup a custom dedup rule that uses 'Email + Wordpress Id'
If you do not collect the email at time of insert
you could store the Wordpress Id in a custom field and use the REST API's 'Get Multiple Leads by filter type' using the custom field to determine if the record is in your system.
Your API calls to insert/update records into Marketo would be something like:
Get Multiple Leads by Filter Type using Wordpress Id
- if empty response : Insert new lead into Marketo
- if Id is returned : update record
I would suggest storing email on the record at somepoint and setting up a custom dedup rule that uses Email + Wordpress Id.
Hope it helps!
As Mark mentioned, I would recommend checking out the Get Multiple Leads by Filter Type REST API.
Here's a blog post that walks through an example of using this API:
Hi, Kenny, Mark and Murtza
Thanks for your useful information!
I will follow your advice!