If one table, let's call it table_1, has a composite alternate key made up of field1 and version, is it considered denormalized data, since field1 is repeating itself in the table (multiple rows with same value for field1 but different value in version), and thus field1 shall be extracted to another table, let's call it table_2, so table_2 will have two columns field_1 and field_1_id, and replace field1 in table_2 with field_1_id?


I think one table is a better design, but someone is suggesting me to have two tables, the reason is the duplication of values in field1, but even with two tables, the field_1_id will still be duplicated, right?

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    Consider that, instead of having repeated values of field1, the new table will have repeated values of field1_id. Do you think that something is changed about normalization?
    – Renzo
    May 24, 2019 at 19:50
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    No, wrong. Simply use a realistic example, natural language and logic to design -- the rest will take care of itself. It is extremely easy to get bogged down in "generic" examples and mind-numbing terminology. Take a look at this: dba.stackexchange.com/questions/215868/… May 25, 2019 at 11:23
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    .. (cont) Keep in mind that DB design is predicate design -- so to have redundancy you have to repeat a whole predicate -- not a value of a single attribute. May 25, 2019 at 11:31


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