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I have run an analysis with SchemaSpy.

The tool gave me a warning message for two tables. The warning message is:

Tables with incrementing column names, potentially indicating denormalization

What is meaning of the above error?

For reference :

http://schemaspy.sourceforge.net/sample/anomalies.html

1 Answer 1

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Based on the sample table in your link, I'd suggest it's taking issue with fields such as:

phone1
phone2

or

notes1
notes2
notes3

This may indicate a design flaw (but not always), and if so, one that can probably be corrected by more descriptive field names or perhaps a child table.

For example, someone might have more than one phone number... what if someone has three? Seven? Maybe data like this should be in a subtable, and perhaps even with some sort of indicator of what type of phone number it is, whether it's a preferred phone number, etc. Alternatively, maybe just renaming the fields to phone_home and phone_cell will be enough to eliminate confusion and allow you to collect all of the data you need.

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    Specifically looks as though it takes that as an indicator the table may not be in first normal form then. May 7, 2013 at 12:26
  • I often see this sort of thing with tables that have fields such for address lines: addressLine1, addressLine2, addressLine3. May 7, 2013 at 13:33
  • It works.. Thanks... Wonder.. How decision making engine considering micro things which we even didn't care...
    – Batakj
    May 8, 2013 at 5:39

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