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DAT 601 - Robin Le Couteur - NaLER Analysis - 10/4/2018


Tuesday, April 10, 2018

NaLER Analysis

In this class we looked at how to do a NaLER Analysis

Here's some of the rules I picked up

Step 1 - Determine the format of the model and make sure the model is consistently in that format

Step 3 (For each entity)-
3.1
Construct a sentence for the primary key attribute/s of each entity:
"Each <entity name> is uniquely identified by <primary key>"
Make sure the primary key actually makes sense as the PK of the entity in question

3.2
One <E-name> identified by <PK> must have one <attribute name>

3.3
One <E-name> identified by <PK> <optionality><relationship-name><cardinality><E-name2> identified by <foreign key>
One Zoo(Zoo_no) may house one or more Animal (Zoo_no, Animal_no)

Step 4 (Populate the sentences from 3.2, 3.3 with these examples)-
Zoo111 houses animal 'regents park 123'
Zoo111 has the name 'regents park'

Step 5 (For each entity with ternary or more m-m relationship(3 or more columns in the PK) and has a composite name)-

One <E-name> identified by <PK1> <optionality> <relationship-name1> <cardinality> <E-name2> identified by <PK2> <optionality> <relationship-name2> <cardinality> <E-name3> identified by <PK3>


After we went through the rules, Todd gave us a NaLER Analysis to build a model off. This was the result of that exercise:

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