When executing a `MERGE INTO` statement in Delta Lake, what happens if the source dataset contains multiple rows that match the same target row based on the join condition?

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B. Delta Lake raises an error because MERGE requires each source row to match at most one target row. Delta Lake enforces a cardinality constraint on `MERGE INTO`: if multiple source rows match the same target row, Delta raises a `MERGE_CARDINALITY_VIOLATION` error. To avoid this, deduplicate the source dataset before performing a MERGE to ensure at most one source row matches each target row.

When executing a `MERGE INTO` statement in Delta Lake, what happens if the source dataset contains multiple rows that match the same target row based on the join condition?

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When executing a MERGE INTO statement in Delta Lake, what happens if the source dataset contains multiple rows that match the same target row based on the join condition?

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When executing a `MERGE INTO` statement in Delta Lake, what happens if the source dataset contains multiple rows that match the same target row based on the join condition?