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Data Modeling Anti-Patterns: EAV, Comma-Separated Lists, Repeating Columns and the One True Lookup Table

Modeling anti-patterns are shortcuts that switch off the database's type, uniqueness and foreign key checks; each of them quietly returns a wrong result in some query. In SQL Server we show the row EAV loses and the JSON column alternative, the LIKE trap of comma-separated tags, the rule phone1/phone2/phone3 cannot express, the wrong foreign key of the one big lookup table, leaving every column nullable, and FLOAT for money.