sql - self join table - performance/other implications -

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Is there any performance / other implications in relation to the object itself? (Self-contained)

Consider the following example: 

  People (name of the table) belongs_to: profile ,: class_name = & gt; 'Person' ,: dependent = & gt; : Delete the id login password first_name last_name profile_id

this question party

You do not specify which database you are using, but AFAIK, there will be no performance problems with not only joining itself, on some alternative solutions Performance benefits can be.

In addition, IMHO is easier to understand than nested SQL statements, but it is completely subjective.

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