Connect Mailchimp to BigQuery
This example transfers a useful update from Mailchimp to BigQuery when a subscriber joins an audience. The goal is to make the source context available to the receiving team without giving every teammate access to both systems. It is a design blueprint, not an activated connector.
The event contract
Send subscriber email, audience and consent status as the initial payload. Keep the Mailchimp source identifier alongside the BigQuery destination reference. Treat the event timestamp as data, not as a unique key. If an optional field is missing, omit it explicitly rather than overwriting an existing destination value with an empty string.
- 01
Choose the trigger
Start with a test event where a subscriber joins an audience. Apply a filter so only records owned by the intended team continue.
- 02
Resolve the destination
Look up the matching BigQuery record using the stored source key. Define what should happen when there are zero, one or several matches.
- 03
Transform the payload
Normalize dates to ISO 8601, preserve currency codes and map the marketing fields into the receiving schema.
- 04
Write and acknowledge
Save the result in BigQuery, then mark the source event as delivered. Keep the acknowledgement separate from the outgoing request.
Failure handling and replay
A repeated event should reuse its original key. A permission error should pause the connection and notify its owner. A rate-limit response should wait for the indicated interval. Send malformed audience members to a review queue and retain only the fields needed to diagnose the error. Never place an access token in an execution log.
A practical acceptance test
Create three sample audience members in Mailchimp: a complete record, one missing an optional value and one containing a non-ASCII name. Deliver each to BigQuery, replay one event, and confirm that the destination contains three intended results. Document the response when a required field is absent.
Is this a two-way sync?
The illustrated recipe is one-way. A two-way design additionally needs conflict resolution, loop prevention and an explicit system of record.
Are performance figures guaranteed?
No. Measure latency and success rate against your actual accounts. The demonstration makes no uptime or throughput guarantees.