sfmc // SQLPROJECT
Fast Approximate Split with _CustomObjectKey Modulo
Use the hidden row key for cheap approximate segmentation of a standard Data Extension.
sqlcustomobjectkeymodulosegmentation
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Evidence tierPROJECTOfficial sources1Other sources0Last verified2026-10-05
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Large standard DE needs an approximate N-way split and perfect balance is not required.
SELECT
SubscriberKey,
EmailAddress
FROM [Eligible_Audience]
WHERE _CustomObjectKey % 4 = 0Modulo maps sequential numeric row keys into repeatable remainder buckets with very little computation.
Salesforce documents this as a performant segmentation technique for standard Data Extensions.
Distribution is approximate, especially when rows are frequently inserted/deleted.
Use NTILE when balanced groups matter more than throughput.