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POUnder what condition we need to use composite keys in database
primarykey
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2011-03-10T13:57:00.523
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2011-06-27T03:42:30.967
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2011-06-27T03:42:30.967
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i have seen that we can have composite keys where the primary key is made up from combined primary keys of two tables. Like persons and Books <pre><code>person_id and book_id will make the primary key. </code></pre> But i want to ask that we there is need to hard code that programming langauge I mean is it ok i can have separate column with any name to work as primary key then i don't have to hard code it and i can perform my functions as normal like <pre><code>id,person_id ,book_id </code></pre>
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<java><mysql><database><hibernate>
Title
Under what condition we need to use composite keys in database
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