PostHog
This page describes how to use Census with PostHog.
In this guide, we will show you how to connect PostHog to Census and create your first sync.
- Have the proper credentials to access your data source. See our docs for each supported data source for further information.
PostHog provides a write-only key.
In PostHog's left navigation bar, click Project Settings.
Then, scroll down to Project Variables > Project API Key.
Copy your Project API Key. We'll use that in a minute
Great! Now let's pull it all together.
- 1.
- 2.You can provide whatever name you like for the connection
- 3.Paste your PostHog Project API Key
- 4.Enter your PostHog custom domain if you're using one, otherwise leave it blank.
- 5.Click Connect

Census will test your API key and show a green checkmark when successful.
✅
See our docs for each supported data source and follow the appropriate short guide depending on your data warehouse technology.
Here you will have to write SQL queries to select the data you want to see in PostHog. Here are some ideas of data you should select:
- Event data like event id, event name, contact id, contact name
Once you have created your model, click Save Model.
In the "What data do you want to sync?" section
- For the Connection, select the data warehouse you connected in step 3
- For the Source, select the model you created in step 4
Next up is the "Where do you want to sync data to?" section
- Pick PostHog as the Connection
- For Object, Event will automatically be chosen
For the " How do you want to update the destination?" section
- Append will automatically be chosen
- Choose the Unique ID Column
- Decide if you'd like to turn on Use timestamp column to identify new data.
- This can be more efficient for large or frequently changing data sets. More info can be found in this doc.
Finally, select the properties you want to update in the Mapper in the "Which properties should be updated?" section
- Choose to update Specific Properties or Sync All Properties.
- Map the required fields Person's Distinct ID and Event Name fields
- Map the rest of the fields from PostHog to the columns from your model
In the "Should existing data be synced?" section
- Chooses whether you want to backfill records or only sync new records going forward
The end result should look something like this

Click the Next button to see the final preview which will have a recap of what will happen when you start the sync
Now go back to your PostHog account and view the event data that should have been created. If everything went well, you should see your data in PostHog.
That's it! In 6 steps, you connected Census to PostHog and started syncing event data from your warehouse to PostHog 🎉
Census currently supports syncing to the following PostHog objects.
Object Name | Supported? | Sync Keys |
Event | ✅ | Event ID |
Person | ✅ | ID, Email |
Page | ✅ | Distinct ID |
Behaviors | Supported? | Objects? |
Update or Create | ✅ | Person |
Update Only | ✅ | Person |
Append | ✅ | Event, Page |
Last modified 1mo ago