10:2710:27, 9 June 2021diffhist+1,065
Unnormalized form
Added a section about UNF as a prerequisite stage to normalization, so the UNF link from the normalization page makes sense. (But I wonder if this should be a separate page?)
09:3609:36, 9 June 2021diffhist−1,230
Unnormalized form
Remove section which is basically nonsensical. It confuses lack of normalization with having no relations. The pros and cons of normalization is better described on the normalization page.Tag: section blanking
15:2615:26, 8 June 2021diffhist−170
Database normalization
Removed incorrect reference to "repeating groups". Repeating groups is a confusing term, but the way Codd uses it, it refers to nested records, which is what 1NF eliminates.
15:1215:12, 8 June 2021diffhist−831
Database normalization
Corrected explanation of first normal form. Previous text conflated different normalization levels and issues unrelated to normalization.
18:2818:28, 7 June 2021diffhist−1,221
First normal form
Remove misleading example. Multiple columns with same domain is explicitly allowed in 1NF, as long as they have distinct names.
17:5317:53, 7 June 2021diffhist+44
First normal form
Change misleading example. A comma separated string is not a violation of 1NF. First Normal form is about disallowing the nested structures known from hierarchical databases.