Auston T.

kapa.ai Do mixpanel support import the same event with different properties? like event_name, time ,distinct_id ,insert_id all the same.But we add new properties. How will it deal those event? If mixpanel accept that, do it had any time range limit?

kapa.ai

migrating events from an old Mixpanel project to a new project, filtered by:

properties["metadata.country"] == "cn"

For one example date/event:

- Event: v2.view.opened
- Date: 2026-04-01
- Old project: 1262196
- New project: 4020883

From the old project Raw Export API, after deduping by properties.$insert_id, we got:

- Deduped rows to import: 284,035
- Unique $insert_id values: 284,035

We imported this deduped file into the new project.

However, in the new project, Mixpanel Insights shows only:

- 273,077 events

We then checked the new project through Raw Export API for the same event/date/filter and found:

- Raw Export rows: 285,313
- Unique $insert_id values: 274,440
- Duplicate extra rows by $insert_id: 10,873

This is confusing because the imported file had no duplicate $insert_id values.

Could you help us understand what might cause this mismatch?

kapa.ai about soft delete we ask delete some event for special condition after that daty, we import the event with that special condition which we change timezone for ensure the the fact. But the question is the insight can be not clear with those event ,the same time range with different breakdown/unit .the total number will different

kapa.ai what i discuss it about event as follow: { "event": "Page View", "properties": { "token": "{{token}}", "distinct_id": "$device:anonymous123" } } it will not connect anyone right? if it need to connect anyone it should login let preproties had use.id ?

kapa.ai What will it happened when event do not had device_id and user_id and user do not login

kapa.ai we had a issue about mapping id event A distinct_id is device_A with $device_id:B event B distinct_id is device_A with $device_id:B ,user.id ->final user :user.id ,and mapping distinct_id devide:B so event A do not connect to user

kapa.ai when project id set Identifying Users (Simplified) how will it treat two different distinct_id ($devicede:xxxxx) with the same user_id?

kapa.ai I checked the issue and it seems related to Mixpanel’s property limits. Mixpanel has a limit of 255 properties per event, and there are also length limits for property names and values. In this case, the cohort appears to contain multiple layers of role/identity information grouped together. This seems to work in the existing project, since the cohort itself can still show numbers correctly. However, once the same cohort is applied to an Insights report, the report breaks and shows a warning/error icon. So the issue may not be with the cohort definition itself, but with how Mixpanel expands or evaluates the cohort properties when used inside an Insights report, potentially exceeding the allowed property length or complexity in filters, breakdowns, or other report operations.

kapa.ai But I tried that if we sent the same event with different properties it will update. The situation is we sent two event in 10 mins

kapa.ai New issue if we sent event with the same time, distinct_id,insert_id but different properties,do it update or not? Even it is a last month event.