Skilirium

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Kompetentsi Andmete modelleerimine knobit · K-628 · Oskus

Recognises a nullable foreign key on a reporting join path

Mida see tähendab

A nullable foreign key that reports reach through with an inner join. Rows with a null drop out of every such report without an error: the physical form of the chasm trap (logical row 25).

Kuidas seda hinnatakse

Flags the deficient case and passes the acceptable one. Deficient: `fact_account_opening.branch_key` null for accounts opened online; every report by branch loses them. `loan.collections_officer_id` null until an arrears case is assigned; loans newly in arrears are missing from the workload report Acceptable: In a dimensional model, an "Unknown" or "Not applicable" member and the foreign key `NOT NULL`; in a normalised model, the nullability kept, the reporting views using outer joins, and the logical model checked against logical row 25

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