ef code first - Entity Framework Migrations: Prevent dropping column or table -

if ef migration decides rename column (or table), fulfills dropping (old) column , adding column new name. leads data loss.

is there way prevent ef migration dropping column , force use renamecolumn instead?

well, didn't find clear , straightforward solution.

my solution hiding dbmigration class every migration generated using code-based migration derived from. introducing new class same name (dbmigration). put inside same assembly , same namespace code files reside. way, reference of code files original dbmigration goes fake dbmigration. then, can prevent dropping column or allow through explicit request:

namespace myproject.dal.migrations {      /// <summary>     /// customized dbmigration protect columns dropped accidentally     /// </summary>     public abstract class dbmigration : global::system.data.entity.migrations.dbmigration     {         public bool allodropcolumn { get; set; }         protected internal new void dropcolumn(string table, string name, object anonymousarguments = null)         {             if (!allodropcolumn)                 throw new exception("myproject: dropping column while updating database prohibited. if want drop column(s), set property 'allowdropcolumn' true.");         }     } } 

and in code file:

public partial class _1 : dbmigration     {         public override void up()         {             allodropcolumn = true; // allow column drop             addcolumn("driver.truckdriver", "fullname2", c => c.string());             dropcolumn("driver.truckdriver", "fullname");         }          public override void down()         {             addcolumn("driver.truckdriver", "fullname", c => c.string());             dropcolumn("driver.truckdriver", "fullname2");         }     }