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  1. #1
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    Unanswered: Semantic Constraint

    Hi all:

    Just joined forums, so a big hello to you all

    Just wondering if someone could explain the following two terms too me?

    *Semantic Constraint
    *Access Control

    Are there limitations each can impose within a relational database?

    Many thanks

    Olly

  2. #2
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    Quote Originally Posted by Olly
    Hi all:

    Just joined forums, so a big hello to you all

    Just wondering if someone could explain the following two terms too me?

    *Semantic Constraint
    *Access Control

    Are there limitations each can impose within a relational database?

    Many thanks

    Olly
    Please forgive me for presuming; but this really looks like a classroom assignment. If its not, I hope you will be understanding and forgive me presumption.

    In either case, you can use google or a half dozen other search engines to research your answer. I would actually like to see you post an answer to your question on here after you've done your research and open it up to comments. Like anything else in life, you'll find it much more rewarding to dig out the answers yourself than to have them handed to you.

    Welcome to the forum!

    Regards,

    hmscott
    Have you hugged your backup today?

  3. #3
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    I can tell you these are not terms that are commonly used.
    If it's not practically useful, then it's practically useless.

    blindman
    www.chess.com: "sqlblindman"
    www.LobsterShot.blogspot.com

  4. #4
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    no no no. I use semantic constraints every day.

    When I am thinking "this customer, co-worker, manager, project manager etc... can go screw himself because he does not know what he\she is talkng about"

    I apply a semantic constraint and it comes out of my mouth as...

    "I appreciate your feedback and I will have to take this up with the enhancement committee and I look forward to interfacing with you in the future..."

    although I never say "interfacing with you", I just heard it come out of someone's mouth the other day and I can't stop snickering when I think about it.
    “If one brings so much courage to this world the world has to kill them or break them, so of course it kills them. The world breaks every one and afterward many are strong at the broken places. But those that will not break it kills. It kills the very good and the very gentle and the very brave impartially. If you are none of these you can be sure it will kill you too but there will be no special hurry.” Earnest Hemingway, A Farewell To Arms.

  5. #5
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    Quote Originally Posted by Thrasymachus
    although I never say "interfacing with you", I just heard it come out of someone's mouth the other day and I can't stop snickering when I think about it.
    Now there's a term that I do use occiasionally... The SO is almost as geeky as I am, and occiasionally we like to "inter" face a bit on the couch before we...

    NEVERMIND!!!

    -PatP

  6. #6
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    "interfacing with you" is definitly on my bullshit bingo card...

    http://www.bullshitbingo.net/cards/bullshit/
    “If one brings so much courage to this world the world has to kill them or break them, so of course it kills them. The world breaks every one and afterward many are strong at the broken places. But those that will not break it kills. It kills the very good and the very gentle and the very brave impartially. If you are none of these you can be sure it will kill you too but there will be no special hurry.” Earnest Hemingway, A Farewell To Arms.

  7. #7
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    Quote Originally Posted by Thrasymachus
    no no no. I use semantic constraints every day.

    When I am thinking "this customer, co-worker, manager, project manager etc... can go screw himself because he does not know what he\she is talkng about"

    I apply a semantic constraint and it comes out of my mouth as...

    "I appreciate your feedback and I will have to take this up with the enhancement committee and I look forward to interfacing with you in the future..."
    Too funny! So a database without constraints is like a person with Touret's Syndrome?
    If it's not practically useful, then it's practically useless.

    blindman
    www.chess.com: "sqlblindman"
    www.LobsterShot.blogspot.com

  8. #8
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    Quote Originally Posted by Thrasymachus
    ... and it comes out of my mouth as...
    A guy boards a plane bound for Pittsburgh and sits down in his seat. He notices immediately that the guy next to him has a black eye. He says, "Hey what a coincidence, we both have black eyes. Mind if I ask how you got yours?"

    The other guy answers, "Well, it was a tongue twister accident. See, I was at the ticket counter and this gorgeous blonde with the biggest breasts in the world was behind the counter. So, instead of saying 'I'd like a ticket to Pittsburgh,' I said 'I'd like a picket to Tittsburgh.' And she socked me one."

    The other guy answers, "Mine was a tongue twister accident too. I was at the breakfast table this morning and I wanted to say to my wife, 'Please pour me a bowl of Cheerios.' But I accidentally said, 'You ruined my life, you Fecking Bitch.'"
    rudy.ca | @rudydotca
    Buy my SitePoint book: Simply SQL

  9. #9
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    Result

    Hi all:

    Firstly this isn't an assignment, however I can see how one would misconstrued it to be so!

    Any how having delved further into RD I have pretty much answered my own question:"Access control is a mechanism for achieving confidentiality and integrity in software systems. Access control policies (ACPs) are security
    requirements that define how access is managed and the high-level rules of who can access what information, under what conditions. In plain words it acts as a barrier or rule by which we can define which user can access what information. "

    But Semantic Constraint is a bit difficult, as i don't know what it is as a
    defenition. It deals somewhat roughly about the syntactical relations
    between constraints i think.

    Any further advice on Semantic would be greatly appreciated.

    Cheers

    Olly

  10. #10
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    Search Books Online for "Semantic": No topics found. Who asked you this?
    If it's not practically useful, then it's practically useless.

    blindman
    www.chess.com: "sqlblindman"
    www.LobsterShot.blogspot.com

  11. #11
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    blindman, don't be so naïve, it's a homework assignment, despite his protestations

    olly, don't go by what's in Books OnLine, it don't know squat about logical design

    search google for the phrase "semantic constraint" and you get 23,600 hits

    have a look at a few of those, and if they don't answer your question, try again with semantic constraint (not a phrase) and you will get almost 4 million hits
    rudy.ca | @rudydotca
    Buy my SitePoint book: Simply SQL

  12. #12
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    Okay, whatever I didn't realise you were the Oracle!!!!!!!!!! If it was an assignment I would have said so.

    I'm new to database design and the comapny I work for said that I should look into both Semantic Constraints and Access Controls, therefore I thought it would be wise to ask some professionals! didn't expect I'd be insulted along the way mind!!!!!!!!!!!!!!!!!!!

    I'll stick to the text books as its clear you know best.

  13. #13
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    Quote Originally Posted by Olly
    Okay, whatever I didn't realise you were the Oracle!!!!!!!!!!
    The Oracle guys are way worse...hehe.

    Don't take it too personally; things can get a bit rough sometimes around here.

    Despite blindmans protestations, my SQL Books online contains one entry for Semantic (though nothing about semantic constraints, which may be what he meant).

    I might have phrased the original question with more information, such as who asked the question, why it was relevant and what your initial searches had revealed. That way everyone knows you've put forward some effort.

    Don't get discourage, stick around. Read lots (especially the sticky's at the top).

    Like I said, welcome to the forum!!!!

    Regards,

    hmscott
    Have you hugged your backup today?

  14. #14
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    Don't mind R937. He's usually a nice guy, except when his liederhosen start chafing.
    If it's not practically useful, then it's practically useless.

    blindman
    www.chess.com: "sqlblindman"
    www.LobsterShot.blogspot.com

  15. #15
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    Mar 2006
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    lol

    Thanks to everyone for input. have been asked to look into these questions as they may come up in interview. I'll attempt to bottom these and post results for everyones verification that I'm on the right track.

    Thanks again to those who have proved helpful.

    Olly

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