In Merge operations, DSP applies the Principal Matched Record Selection Rule to decide which record becomes the principal (master). This record is retained after the merge, while the others are marked for deletion.

Available selection rules:

• Most Complete – keeps the record with the most populated fields.

• Most Child Records – keeps the record with the most related child records (requires specifying the child relationship name in Principal Selection Child Relationship).

• Most Recently Modified – keeps the record with the latest LastModifiedDate.

• First Record – keeps the first record according to a custom sort defined in Matched Records Sorting Components (using DSP formulas).

When using DuplicateRecordItem as the matching object:

• By default, the principal is chosen at the DuplicateRecordItem level.

• You can instead select the principal on the underlying object (e.g., Account, Lead) by specifying its API name in Duplicate Record Object API Name.