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joins

 
narayana arya
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Does anybody explain or send link about joins (inner,self,...) detailly..
 
Maximilian Xavier Stocker
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In short JOINS join two tables together. For how and what exactly happens this is kind of vendor specific. I mean one can describe some theory but to put into practice you need to write the right JOIN for your Database. What database are you using?
 
Anonymous
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Inner Join: to get the same tuples from different relations

Outer Joins: NEVER used alone.
  • Left (Outer) Join: to get the tuples that match + the ones that exist on the left relation even there does not exist any correspondent on the right relation
  • Right (Outer) Join: lokk at the above definition, and convert.
  • Full (Outer) Join: get really all the tuples; from both relations

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    Michael Duffy
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    Originally posted by naranayana vijaya:
    Does anybody explain or send link about joins (inner,self,...) detailly..


    There's a great Wiki entry that explains it nicely:

    http://en.wikipedia.org/wiki/Join_%28SQL%29
     
    I agree. Here's the link: http://aspose.com/file-tools
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