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Understanding @JoinColumn

 
Greenhorn
Posts: 14
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Hi,

I am new to the ORM Concept. A basic question:

Given the following two a) and b) legal Entity-declarations:

a)


b)

Can anyone explain me, what's the difference in usage between the two? (I don't really understand what @JoinColumn is for.

Thanks for clarifying.

 
Author
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IntelliJ IDE Ruby
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Please UseCodeTags when posting code or configuration. Unformatted code and configuration is unnecessarily difficult to read. You can edit your post by using the button.
 
Ranch Hand
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@JoinColumn is to specify the name of the foreign key column. If you do not provide a JoinColumn the name of the column will be defaulted.
You can also specify DDL related information in the JoinColumn.

Giving an empty @JoinColumn is not very useful, as it is still being defaulted, there is not any difference to not providing one at all.
 
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