5. etapp: Loogilise andmemudeli tuletamine
Kompetentsi Andmete modelleerimine knobit · K-552 · Teadmine
Explains candidate key and prime attribute
Mida see tähendab
A candidate key is a minimal set of attributes that determines all others; a prime attribute belongs to a candidate key.
Kuidas seda hinnatakse
Finds every candidate key of a sample entity from its dependencies and classifies its attributes as prime or non-prime
Tugineb
- Explains functional dependencyK-551 · Teadmine
Vajalik
- Recognises a uniqueness rule with no unique key behind itK-311 · Oskus
- Records the functional dependencies of an entityK-532 · Oskus
- Explains second normal formK-555 · Teadmine
- Explains third normal formK-556 · Teadmine
- Explains domain-key normal formK-561 · Teadmine
- Explains lossless-join decompositionK-563 · Teadmine
- Explains natural keys, surrogate keys and key stabilityK-568 · Teadmine
- Explains identifying and non-identifying relationshipsK-904 · Teadmine