entity-framework

问题 I have been tasked with porting an old app to MVC 3, and want to use EF's code first to replicate its existing database schema. The current code base is littered with hard coded SQL commands, and so the model I come up with has to be "compatible" with what the current system expects. I know I could use EF's Database First to do this, but the existing schema is so simple that I see no reason not to use code first, as I want a solid foundation to build on as we migrate away from our old hard

问题 When I try and use EntityFramework and MySQL on a Linux or Windows environment I run into the following problem: Project 1: Contains EntityFramework edmx and logic to insert update data using the dbcontext class Project 2: References Project 1. When I build the solution using msbuild the EntityFramework metadata files are embeded in Project1.dll When I do a clean build with xbuild in a Linux environment or in a Windows environment the EntityFramework metadata files are missing When you run

问题 When I try and use EntityFramework and MySQL on a Linux or Windows environment I run into the following problem: Project 1: Contains EntityFramework edmx and logic to insert update data using the dbcontext class Project 2: References Project 1. When I build the solution using msbuild the EntityFramework metadata files are embeded in Project1.dll When I do a clean build with xbuild in a Linux environment or in a Windows environment the EntityFramework metadata files are missing When you run

问题 I noticed EF removed an index on a foreign key when I added a composite index with the foreign key. So I need to understand composite indexes better :) I added the composite index using this answer and generated my EF code first migration file. Adding composite index: this.Property(x => x.Name) .HasUniqueIndexAnnotation("IX_UniqueNamePerKey", 0); this.Property(x => x.TeacherId) .HasUniqueIndexAnnotation("IX_UniqueNamePerKey", 1); Migration file: public partial class CompositeIndex :

问题 I am using the ef core 2.0 CLI command scaffold-dbcontext to reverse engineer poco classes from an existing DB (database first). I want to put the generated classes from scaffold-dbcontext in a "Model" folder within my project but I want the namespace of the classes to be something different than "MyProjectName.Model". For example, I want the scaffold-dbcontext generated files to live in the Model folder but I want the namespace of the genereated files to be "MyProjectName.Entities". Is there

问题 I've finished an EF Code First Project with a SQL Express database in a lab environment. Once the project is done, I've changed the DB Connection String to connect to the new Production SQL Express Database. Now, I have got the Model tables generated automatically but the AspNetUsers, AspNetRoles, AspNetUserRoles etc. are not generated automatically. I am a new learner and I need your help to know how I can get the tables back in the database. If I do update-database from the Package Manager

问题 I have a class with a nullable int property that that for filtering reasons, I need to convert to a string to do some comparisons. I have EF 6.1.2 installed, so using a .ToString() will work for that. queryableData = queryableData.Where(a => a.PropName.HasValue && a.PropName.Value.ToString().Contains("8675309")); When examining the actual SQL being executed, the number is being CAST into an NCLOB type, which is resulting in the following error: ORA-00932: inconsistent datatypes: expected

问题 I have a class with a nullable int property that that for filtering reasons, I need to convert to a string to do some comparisons. I have EF 6.1.2 installed, so using a .ToString() will work for that. queryableData = queryableData.Where(a => a.PropName.HasValue && a.PropName.Value.ToString().Contains("8675309")); When examining the actual SQL being executed, the number is being CAST into an NCLOB type, which is resulting in the following error: ORA-00932: inconsistent datatypes: expected

问题 I have a class with a nullable int property that that for filtering reasons, I need to convert to a string to do some comparisons. I have EF 6.1.2 installed, so using a .ToString() will work for that. queryableData = queryableData.Where(a => a.PropName.HasValue && a.PropName.Value.ToString().Contains("8675309")); When examining the actual SQL being executed, the number is being CAST into an NCLOB type, which is resulting in the following error: ORA-00932: inconsistent datatypes: expected

问题 The Issue... As the title states, I've installed the .NET Core 2.1 SDK and created a new .NET Core 2.1 project. When I go to Project > Add Item... > Data , I do not have the ADO.NET Entity Data Model option. I am using Visual Studio 2017 15.7.3 , which I've installed only hours ago. The Error and Warning logs are clean. Any assistance is appreciated. What I've done so far... Researched. You'll notice I've pulled most of my attempts to solve this issue from primarily these three resources: