Data Cloud: Understanding the Event Time Field and Record Modified Field

1. Overview of each item

Point:
The "Event Time Field" plays a role similar to that of the primary key of data, and the "Record Modified Field" determines whether overwriting is allowed or not.

2. Range of application of full update and upsert

3. Event Time Field

3-1. Role and characteristics

• Role: Functions like a "composite primary key" that is added to the primary key.
• Target field type: DateTime or Date
• Category: Engagement only
• Scope of application: Active only for "upsert" (inactive for full update)

3-2. Relationship with system item cdp_sys_PartitionDate

The selected Event Time Field is internally recorded to cdp_sys_PartitionDate. This field is a formula field, and the time is converted to 00:00:00 as follows for DateTime. This process is performed before the time zone conversion, so 9 hours are added later in the case of JST.

Conversion flow (example)

3-3. Operating rules

• If the date matches: Overwrite the existing record
• If date is different: Insert as a new record even with the same primary key

Note:
If the date in cdp_sys_PartitionDate differs even slightly, it is registered as a new record. (This is the reason why it is like a compound primary key.)

3-4. Recommended settings

Specify date fields that will not change in the future (e.g., creation date, event date, open date, click date).
Once set, they cannot be changed, so thorough consideration must be given before they are set.

4. Record Modified Field

4-1. Role and characteristics

The "Record Modified Field" is a field that is used to determine if an overwrite is possible.
The value set on import is managed as a high watermark (maximum value).

4-2. Operating rules

Example: If the existing "Record Modified Field" is 2025/11/19 10:25:45

4-3. Cases where setup is not required

• If the order in which data files are processed is always guaranteed
• For data where order is not a concern

4-4. Recommended settings

In environments where the order of data processing may be disrupted, it is recommended that "Record Last Modified Date" be set as a record modified item.

5. Order of processing between Event Time Field and Record Modified Field

1. Event Time Field (overwrite/insert decision)... Prioritized
2. Record Modified Field (overwrite ability decision)

If the Event Time Field is different and created as a new record, the "Record Modified Field" is ignored because there is no comparison target.

6. Summary

Correctly configuring these items enables maintaining data integrity and optimizing Data Cloud processing accuracy and performance.

Contributor: Nobuyuki Watanabe | Trailblazer Community Forum Ambassador

Serving as a Marketing Cloud Engagement consultant at FPT Japan Holdings Group. He is working to optimize customer communications using Marketing Cloud Engagement by supporting scenario design, data design, campaign operations, and personalization measures, with a focus on email, LINE, and PUSH.

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