A duplicate merge rule defines which record survives and what happens to complementary or conflicting values when duplicate rows are consolidated.

Finding duplicates and merging them are separate decisions. Matching rules build the groups. Merge rules decide the output.

Record-to-keep rules

The retained record becomes the merge destination. Datablist supports rules such as:

  • Most complete record
  • Last updated record
  • First created record
  • Highest or lowest value on a property
  • Record containing a required property value

The Free plan applies Most Complete automatically. Configuring another record-to-keep rule requires a paid plan.

Rules for conflicting values

For a worked job-title example, read conflict resolution in data merging before choosing a field rule.

Complementary data can fill empty properties automatically. When duplicate records contain different non-empty values in the same property, choose one of these strategies:

  • Combine distinct text values with a delimiter.
  • Keep the selected record's value.
  • Select the newest, oldest, highest, lowest, longest, shortest, or most frequent value with a field-survivorship rule on paid plans.
  • Leave the group in Needs review for manual processing.

⚠️ Do not merge blindly

A broad rule applies across the duplicate groups. Check the preview before processing so CRM IDs, owner fields, statuses, dates, and numbers keep the expected value.

Datablist recalculates Ready and Needs review after matching thresholds or rules change. Process Ready groups first when some conflicts remain.

Follow how to merge duplicate leads without losing data, or see every merge and record-to-keep rule in the product reference.

Example: the retained record and the retained values

Suppose two confirmed duplicates have these values:

  • Record A: CRM ID = 101, Email = jane@example.com, Phone = empty, Job Title = Head of Sales.
  • Record B: CRM ID = 202, Email = jane@example.com, Phone = +33 1 23 45 67 89, Job Title = VP Sales.

If A is the record to keep, its empty phone can receive B's phone. The job title and CRM ID still conflict. Keeping A's values produces CRM ID 101 and Head of Sales; choosing a different field rule can produce a different title without changing which Datablist item survives.

Do not combine two CRM IDs into one cell when the destination system expects one update identifier. Keep the intended destination ID and save the data merge change log to inspect removed IDs and previous values.

A “newest value” rule also needs the right clock. Datablist's most-recent field rule uses the item's Datablist update timestamp; it does not automatically read an imported CRM timestamp. If source recency determines the correct title, review that source date and the value together rather than assuming the latest local edit identifies the authoritative field.