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    <p>Rather than use triggers to do this, I would be more inclined to perform logical DML SQL statements inside transactions. Triggers, whilst sometimes proving useful, are not really necessary in this scenario (unless they are required for your coursework).</p> <p>As a first approach, think about what is required to complete the application -</p> <ul> <li>A UI layer to present data to the user, allow a user to search, insert, update (and possibly delete) hurricane data.</li> </ul> <p>In this layer, we'll most likely want to </p> <p>1.present users with a list of previous hurricanes, perhaps with some key details displayed and give users the ability to select a particular hurricane and see all the details.<br> 2.give users the ability to insert new hurricane data. Think about how category will be displayed to a user to choose and how inputted data will be taken from this layer and ultimately end up in the data layer. Think also about how and if we should validate the user input. What needs to be validated? Well, ensuring against SQL injection, that values are in permitted ranges and lengths, etc. if this were a real application, then user input validation would be a necessity.</p> <ul> <li>A data layer used to store the data in a defined entity relationship.</li> <li>A data access layer used to perform all data access logic in regard to manipulating the application data.</li> <li>A Business logic layer that contains the classes required for the application. Will contain any of the rules associated with the entities and will be used to present data to the UI layer.</li> </ul> <p>We could take an extremely simplified approach and have the UI layer call straight into the data layer through stored procedures (which would be acting as our data access layer and also our business logic layer as they will encapsulate the rules regarding whether a hurricane record already exists and needs updating or a new record needs creating, possibly some validation too).</p>
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    1. POHelp me with my SQL project (please)
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    1. USRuss Cam
    1. USRuss Cam
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    1. CODo you think I could use a View instead of a table for the Hurricanes_History layer?
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      1. USJoel M.
    2. COThe data layer entails the application data's as a whole - for some applications, this could be a simple flat file structure of text files, XML files, a database,etc. The Hurricane history will most likely be in a table of it's own, if we're following at least 3rd Normal Form. A View is essentially an abstraction over a table structure and could be used to present data to users, although in this case, the joins across tables is straightforward so not really necessary, unless it'll give you extra points :)
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