entity-framework

问题 When I use IdentityUser model in Asp.Net Identity with EntityFramework , it creates some standard fields in the database. All the fields are self explanatory except for the below two fields. NormalizedUsername - Which contains the uppercase value of the Username NormalizedEmail - Which contains the uppercase value of the Email My doubts are: Why do we need these Normalized fields? Where does it get used? What is the purpose of persisting it in the database? 回答1: By my understanding, both

问题 When I use IdentityUser model in Asp.Net Identity with EntityFramework , it creates some standard fields in the database. All the fields are self explanatory except for the below two fields. NormalizedUsername - Which contains the uppercase value of the Username NormalizedEmail - Which contains the uppercase value of the Email My doubts are: Why do we need these Normalized fields? Where does it get used? What is the purpose of persisting it in the database? 回答1: By my understanding, both

问题 I am using EF code first for my project. I have following code in my DataModel [HiddenInput(DisplayValue = false)] public DateTime? PasswordDate { get; set; } To make this non-nullable I removed '?' and ran Add-Migration command from Package manager console. following migration file was generated. public partial class PasswordDate : DbMigration { public override void Up() { AlterColumn("dbo.CertificateInfoes", "PasswordDate", c => c.DateTime(nullable: false)); } public override void Down() {

问题 I am using EF code first for my project. I have following code in my DataModel [HiddenInput(DisplayValue = false)] public DateTime? PasswordDate { get; set; } To make this non-nullable I removed '?' and ran Add-Migration command from Package manager console. following migration file was generated. public partial class PasswordDate : DbMigration { public override void Up() { AlterColumn("dbo.CertificateInfoes", "PasswordDate", c => c.DateTime(nullable: false)); } public override void Down() {

问题 I am using EF code first for my project. I have following code in my DataModel [HiddenInput(DisplayValue = false)] public DateTime? PasswordDate { get; set; } To make this non-nullable I removed '?' and ran Add-Migration command from Package manager console. following migration file was generated. public partial class PasswordDate : DbMigration { public override void Up() { AlterColumn("dbo.CertificateInfoes", "PasswordDate", c => c.DateTime(nullable: false)); } public override void Down() {

问题 Is it possible to sort IQueryable collection by it's sub collections? For example I have a Books collection. I also have an Authors collection which has a column BookId , so the BookId is a foreign key in Authors table. The relation is one-to-many (one book many authors). I need to sort the Books collection by the first author. The book is not required to have an author. Can this be done in Entity Framework and Linq? 回答1: The answer to your concrete question (after clarification that The

问题 We have some info that is contained within an excel sheet. the excel sheet contains two columns; customer name + customer balance. Now I need to display this info inside my asp.net mvc view, basically to query the excel sheet based on the customer name and display its total balance inside my view. In this way we will be uploading the excel sheet inside our system each month or each day , and we will be querying the excel sheet instead of the DB. So is this possible using EF ? or it is better

问题 We have some info that is contained within an excel sheet. the excel sheet contains two columns; customer name + customer balance. Now I need to display this info inside my asp.net mvc view, basically to query the excel sheet based on the customer name and display its total balance inside my view. In this way we will be uploading the excel sheet inside our system each month or each day , and we will be querying the excel sheet instead of the DB. So is this possible using EF ? or it is better

问题 We have some info that is contained within an excel sheet. the excel sheet contains two columns; customer name + customer balance. Now I need to display this info inside my asp.net mvc view, basically to query the excel sheet based on the customer name and display its total balance inside my view. In this way we will be uploading the excel sheet inside our system each month or each day , and we will be querying the excel sheet instead of the DB. So is this possible using EF ? or it is better

问题 Has anyone used .NET Core with DB2 and EF Core? We've tried to find compatible drivers, but none seem to exist. Has anyone found a way to use DB2 with .NET Core 3.0? Thank you! 回答1: There is no core 3.0 or standard 2.1 support thanks to IBM's terrible .Net support. Supposedly an alpha driver will be available in March 2020 if you contact their support. You can some of the conversation at this link. 回答2: IBM have now released a new version 3.1.0.300 of IBM.EntityFrameworkCore on nuget that