Vector enforces primary, unique, and foreign key constraints using SELECT statements against the constraint column(s). Enforced constraints are validated for all operations. As a result constraint checking can have a significant impact on resource consumption for frequent small incremental loads. Take this into consideration when designing your schema, and consider whether to declare enforced constraints and validate data integrity in the data load process. Consider using not enforced constraints or dropping and recreating constraints to minimize the impact of constraint validation during data loads.