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shapper
Constraint Violating Yak Guru
450 Posts |
 Posted - 2007-03-15 : 12:07:19
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| Hello,I have 3 SQL 2005: Documents, Categories and DocumentsInCategoriesDocuments PK is DocumentIdCategories PK is CategoryIdDocumentsInCategories is to be used as a way to relate each document to one or more categories. So in this table I am planning to have 2 columns: DocumentId and CategoryIdIs this a good way to do this?And does the table DocumentsInCategories need to have a column named DocumentsInCategoriesId which would be its PK?If not, how should I set my DocumentsInCategories PK?Thanks,Miguel |
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snSQL
Master Smack Fu Yak Hacker
1837 Posts |
Posted - 2007-03-15 : 13:47:51
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| That is the accepted way to create a many-to-many relationship (which is what you have) and you don't need a separate column for the PK, the compound PK of CategoryId and DocumentId will be fine, and in fact needs to be unique anyway because you don't want a document added to the same category more than once. |
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VincentFrandsen
Starting Member
39 Posts |
Posted - 2007-03-16 : 06:56:42
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| I'd say you must set your primary key in documentsincategories. Can a document have more than one category in your system if yes then that is ok.If a document only has one category then there should be a reference to from docs to categories...Vincent Fradnsen |
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snSQL
Master Smack Fu Yak Hacker
1837 Posts |
Posted - 2007-03-16 : 13:17:00
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VincentFrandsen: quote:
Can a document have more than one category in your system if yes then that is ok.
Original post: quote:
DocumentsInCategories is to be used as a way to relate each document to one or more categories.
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2 tables relation