datamodel

I'm investigating the different types of NoSQL database types and I'm trying to wrap my head around the data model of column-family stores, such as Bigtable, HBase and Cassandra. First model Some people describe a column family as a collection of rows , where each row contains columns [ 1 ], [ 2 ] . An example of this model (column families are uppercased): { "USER": { "codinghorror": { "name": "Jeff", "blog": "http://codinghorror.com/" }, "jonskeet": { "name": "Jon Skeet", "email": "jskeet@site.com" } }, "BOOKMARK": { "codinghorror": { "http://codinghorror.com/": "My awesome blog", "http:/

After years of coding Delphi programs as untestable code in forms and datamodules, including global variables, and the only classes are the forms themselves, containing all the code I need for the form UI itself. How would I convert the code to a set of classes that do the actual work? would I need to stop using the datasources/datasets and do everything in classes? do I need an ORM? There's usually zero need for reuse of the code in the forms, so does it make sense to convert the logic to classes? If I encounter a form (or other class) with too much responsibility, I usualy follow the pattern

I working with mvc 5. I am loading data from Database Using ORM and fill a drop down list from the controller, like this. ViewBag.Country_id = new SelectList(_db.Countries, "Country_id", "Description"); As i wanted an empty field first I am doing this in my HTML. <div class="form-group"> @Html.LabelFor(model => model.Countries, "Country", htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.DropDownList("Country_id", null, htmlAttributes: new { @class = "form-control" }, optionLabel: "Choose a Country") @Html.ValidationMessageFor(model => model.Country_id, "

We are in evaluating technologies that we'll use to store data that we gather during the analysis of C/C++ code. In the case of C++, the amount of data can be relatively large, ~20Mb per TU. After reading the following SO answer it made me consider that HDF5 might be a suitable technology for us to use. I was wondering if people here could help me answer a few initial questions that I have: Performance. The general usage for the data will be write once and read "several" times, similar to the lifetime of a '.o' file generated by a compiler. How does HDF5 compare against using something like an

I am confused to understand what is the meaning of this words: Entity , Model , DataModel , ViewModel Can any body help me to understanding them please? Thank you all. I hope I've not missed your point here king.net... Anyway, presuming you're talking about entity modelling or entity-relationship modelling (ERDs): an entity represents any real world entity - e.g. student, course, an entity will have attributes - e.g. student has first name, surname, date-of-birth an entity will have relationships - e.g. student "is enrolled on" course (where student and course are entities with attributes and

I designed a data model which is represented by an XSD scheme. The data model also provides the types that are being used as web service parameters in a WSDL descriptor. I would like to send the XSD scheme around and ask the people involved to peer review the data model. What tool or presentation method would you suggest to be used as a basis for peer reviews? The data model should be readable for non-skilled people, at least when it comes to the semantic meanings of the parameters Edit: To be more specific: Of course, syntactically, the scheme validates. Actually I'm already working on code