实体框架6：修剪无法正常工作

Question

I have a process which should copy data from one database entity to another. Therefore I use Entity Framework 6 and LINQ expressions in C# :

public partial class ReferenceEntities : DbContext {
     public Nullable<System.DateTime> ActivationDate { get; set; }

     public string Code { get; set; }
}

this.ReferenceEntities.ReferenceEntity.AsEnumerable().Select(referenceEntry => new StagingReferenceLoader() {
    ActivationDate = referenceEntry.ActivationDate,
    Code = referenceEntry.Code?.TrimStart('0').Trim()
});

this.ProcessingEntities.StagingReferenceLoader.AddRange(stagingEntries);
this.ProcessingEntities.SaveChanges();

Code is char(11) column in both entities which are affected by this process.

Example:

In StagingReferenceLoader the Code value looks like this: 00000253089

With the Trim operations I want to make it look like this: 253089 . This looks fine on the first way, when I have executed it. But if I ran this SQL query on the database directly it gives my the result as following:

SELECT DATALENGTH(code), len(code), code
FROM staging.ReferenceLoader

datalength | len | code
11         | 6   | 253177     
11         | 6   | 270724     

Why does Entity Framework just does not do the trim operation?

Answer 1

The type of Code field must be varchar(11), because char(11) has a fixed length. The DB so will always fill it to the full length. Please, change it to varchar.