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Go Back  dBforums > General > Database Concepts & Design > How to decompose table with reference to Heath's Theorem? [Homework]

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How to decompose table with reference to Heath's Theorem? [Homework]

Hi Everybody,

I'm having trouble with a certain aspect of a worksheet that I have for my DBA module. Any advice would be greatly appreciated, thanks.

I have a general understanding of Heath Theorem but I'm having trouble getting my head around this question:

Quote:
Use the functional dependencies to carry out a non-loss decomposition in line with Heath’s Theorem,
to produce a set of tables in 3NF (3 rd Normal Form).

Say why each decomposed table is in 3NF and no longer just 2NF
Say I have the following FD:

Quote:
{orderId} -> {employeeId, unitPrice}
Does this mean I get the table being decomposed (parent) use SQL to convert it to multiple tables (decomposed). From the above the result would include a table with the fields:

Quote:
orderId, employeeId and unitPrice
To explain 3NF vs 2NF do I just confirm there are no longer any transitive dependencies in the new table. This is my understanding of the 3NF requirement.

How do I go about explaining all of the above with relation to Heath's Theorem ?
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heaths theorem, homework, non-loss decomposition

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