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As of today weI can connect to a MySQL database, but cannot generate the Entity Data Model from a MySQL database in Visual Studio 2017 To access a MySQL database from Visual Studio 2017 IMPORTANT: First install MySQL for Visual Studio, and after that install MySQL Connector/Net. If MySQL Connector/Net is already installed on your workstation, uninstall …
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Visual Studio 2017 has many project type options, and not all of them support the Entity Framework user interface to generate the Entity Framework Data Model (EDMX) file. If you create an ASP.NET Web Application(.NET Framework) you can add the EDMX file to it. The .NET Core projects do not support the Entity Framework Data Model …
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When a database table has composite keys (multiple columns are in the key) you cannot use the usual key definition [Key] [Display(Name = “UserId”)] public string UserId { get; set; } [Key] [Display(Name = “RoleId”)] public string RoleId { get; set; } When you run the application you get the error message: {“error”:”Entity type ‘AspNetUserRoles’ has composite …
It is not recommended to execute Entity Framework migration scripts in production, It is important that you execute all SQL steps manually on the production database section-by-section to immediately see the result and be able to recover in case a destructive action goes wrong. The Visual Studio .NET application templates contain Entity Framework migration scripts to …
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The .NET Core Entity framework makes database access easy. When you auto-generate a Razor page in a .NET web application to edit a data row, the scaffolding places controls on the page for every column. There are columns in most of the tables that we don’t want to display or edit, like keys, checksums, password …
When you add a dependency reference to a Java project, it may compile without any errors, but runtime you may get an error message similar to this: HTTP Status 500 – Internal Server Error Type Exception Report Message An exception occurred processing JSP page [/index.jsp] at line [1] Description The server encountered an unexpected condition …
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When you create a Java Spring MVC web application or make changes to an existing one, it is important to know the location of configuration values. Java package name The Java package name is stored in Every .java file package MY_PACKAGE_NAME pom.xml file <configuration> <mainClass>com.objectdb.Enhancer</mainClass> <arguments> <argument>MY_PACKAGE_NAME.MY_MAIN_CLASS_NAME</argument> </arguments> </configuration> .jsp file <%@page import=”MY_PACKAGE_NAME.*”%> <jsp:useBean id=”MY_BEAN_ID” type=”MY_PACKAGE_NAME.MY_DAO_CLASS_NAME” …
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This error can happen on Linux and Windows, and the cause could be the same. On Windows Server 2012R2 I opened a command prompt. To be able to delete a directory from the Tomcat webapps folder, I have issued the shutdown command. When I started the server with the startup command, and navigated to my local …
NetBeans can use multiple deployment servers. When your web application uses the Entity Framework and you select the Glassfish server as the deployment server, you can get the error message when you try to run your application in the IDEÉ Severe: Exception while preparing the app : The persistence-context-ref-name […] in module […] resolves to a …
If you use two-factor authentication see Create a Personal Access Token to use it as password in the command line tools at Switching to 2-factor authentication in GitHub Navigate to https://git-scm.com/download/win to download Git for Windows. The page automatically downloads the installer for the operating system you use. Install the application Accept the default values, including these: Make …