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Is this a violation of 1NF? Are those repeating groups?

+--------+----------+--------------+-------------+
| ItemId | ItemName | ItemCategory | Department  |
+--------+----------+--------------+-------------+
|      1 | Keyboard | Hardware     | Monaco      |
|      1 | Keyboard | Hardware     | Switzerland |
|      2 | License  | Software     | USA         |
|      2 | License  | Software     | Russia      |
|      3 | Arduino  | Hardware     | Russia      |
+--------+----------+--------------+-------------+

And, how about this?

+--------+----------+--------------+--------------+--------------------+
| ItemId | ItemName | ItemCategory | DepartmentId | DepartmentLocation |
+--------+----------+--------------+--------------+--------------------+
|      1 | Keyboard | Hardware     |            1 | Monaco             |
|      1 | Keyboard | Hardware     |            2 | USA                |
|      2 | License  | Software     |            3 | Switzerland        |
|      2 | License  | Software     |            4 | Russia             |
|      3 | Arduino  | Hardware     |            4 | Russia             |
+--------+----------+--------------+--------------+--------------------+

I did not understand it from this answer: Normalization: What does "repeating groups" mean?

  • Please ask just 1 clear specific non-duplicate question per post. For "1NF": ["1NF" has no single meaning.](https://stackoverflow.com/a/40640962/3404097) Nor does "unnormalized" or "UNF" or "0NF" or for that matter "relation". Tell us your definition & textbook name & edition. For "repeating groups": Tell us where you found it used & quote how it was defined & used. Tell us what you think it means. "Are those repeating groups?" is not clear. Tell us what each thing is that you are thinking might be a "repeating group". There are no "repeating rows" here; there are repeating subrows. – philipxy Feb 06 '20 at 01:11
  • Re "repeating groups": This seems to be an exact duplicate of the linked question. It does not have 1 meaning. It meant something in certain pre-relational DBMSs that never turns up now & it is now misused. Its original & present uses are not what you have or what the other asker has. The answers tell you all that. If you want an answer clarified then post a comment on it or quote it here; ask about the 1st place you are stuck. PS I wrote one of those answers. PS Follow a published academic textbook on information modelling, the relational model & DB design. (Not manuals or web posts.) – philipxy Feb 06 '20 at 01:17
  • 1NF: "each attribute of a table must have atomic values". These tables are 1NF since each field has 1 value only. But other NF should be applied before you use this database (2 and 3 at least). – Nic3500 Feb 07 '20 at 01:15

0 Answers0