Thread: SQL vragen

  1. #1
    LilWeezy's Avatar
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    SQL vragen

    Dag iedereen,

    Ik zit al een tijdje te zoeken naar een duidelijke uitleg over volgende zaken :

    Wat is een inner join, left outer, right outer join ?

    Op het internet staat meestal uitleg die vrij vaag is.

    Alvast bedankt!

    Grtz
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  2. #2
    kows's Avatar
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    T1:
    1
    2
    3

    T2:
    1
    4

    T1 join T2 =
    1 1

    T1 left join T2 =
    1 1
    2 null
    3 null

    T1 right join T2 =
    1 1
    null 4

    T1 right outer join T2 =
    1 1
    2 null
    3 null
    null 4

    join is dus alle matches,
    left join alles uit "linkse" kolom met evt info uit "rechtse",
    right join is omgekeerd,
    right outer join is alle mogelijke combo's
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  3. #3

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    Misschien kan dit wel helpen.
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  4. #4
    Jerre Muesli's Avatar
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  5. #5
    profound's Avatar
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    Quote Originally Posted by Jerre Muesli View Post
    This quote is hidden because you are ignoring this member. Show
    Nice
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  6. #6
    th43ns's Avatar
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    Quote Originally Posted by kows View Post
    This quote is hidden because you are ignoring this member. Show
    T1:
    1
    2
    3

    T2:
    1
    4

    T1 join T2 =
    1 1

    T1 left join T2 =
    1 1
    2 null
    3 null

    T1 right join T2 =
    1 1
    null 4

    T1 right outer join T2 =
    1 1
    2 null
    3 null
    null 4

    join is dus alle matches,
    left join alles uit "linkse" kolom met evt info uit "rechtse",
    right join is omgekeerd,
    right outer join is alle mogelijke combo's
    ge bedoelt full outer join is alle mogelijke combo's ;-)
    no votes  

  7. #7
    kows's Avatar
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    uh, full idd, snel getypt in da kotje
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  8. #8
    LilWeezy's Avatar
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    Bedankt iedereen nu is het al veel duidelijker !
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