Question

I want to implement a function that accepts a DbSet (non-generic), a string, and object, and returns DbSet. something like the following pseudu:

public static DbSet Any(DbSet set, string propertyName, objectParameter)
{
  var tableName = set.TableName;
  var columnName = set.GetColumnNameForProperty(propertyName); 
  var query = string.Format("SELECT TOP(1) {0} FROM {1} WHERE {0} = {2}",
                columnName, 
                tableName,
                objectParameter);
}

I think that SQL query is enough since I’ll be able to execute it directly on the Database (context.Database.ExecuteSql).

What I want to do is get the table name from the given DbSet, then the column name in the database.

Answer 1

It is not possible from non generic DbSet but this problem can be easily solved by using:

public static IEnumerable<T> Any(DbSet<T> set, string property, objectParameter)
  where T : class
{ ... }

Returning DbSet doesn’t make sense because once you query data it is not DbSet anymore.

The bigger problem is getting table name from generic DbSet / ObjectSet because this information is not available from those classes. It is almost impossible to get it at all because it requires accessing non public members of items from MetadataWorkspace.