Cannot create Multiple Ids but yet I only have one

Question

As you see I am creating a new class with one primary key I droped the db to recreate it but

public class CustomerContracts
{
    [Key, Column("ItemId")]  //This change the name of the column when you are using migration.  If you have a form created already, you have to change the connection in the for to aim the new column name.  

    public int ItemId { get; set; }

    public string Description { get; set; }

    public string CustomerRef { get; set; }


    public int ContractTypeId { get; set; }

    public DateTime StartDate { get; set; }

    public DateTime EndDate { get; set; }

    public bool isActive { get; set; }
    [DecimalPrecision(18, 2)]
    public decimal Price { get; set; }

}

But I am receiving the following error when I try to update the database.

Specify the '-Verbose' flag to view the SQL statements being applied to the target database. Applying explicit migrations: [201804260855058_firstmigration]. Applying explicit migration: 201804260855058_firstmigration. System.Data.SqlClient.SqlException (0x80131904): Multiple identity columns specified for table 'CustomerContracts'. Only one identity column per table is allowed. at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean async, Int32 timeout, Boolean asyncWrite) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.<NonQuery>b__0(DbCommand t, DbCommandInterceptionContext1 c) at System.Data.Entity.Infrastructure.Interception.InternalDispatcher1.Dispatch[TTarget,TInterceptionContext,TResult](TTarget target, Func3 operation, TInterceptionContext interceptionContext, Action3 executing, Action3 executed) at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.NonQuery(DbCommand command, DbCommandInterceptionContext interceptionContext) at System.Data.Entity.Internal.InterceptableDbCommand.ExecuteNonQuery() at System.Data.Entity.Migrations.DbMigrator.ExecuteSql(MigrationStatement migrationStatement, DbConnection connection, DbTransaction transaction, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.ExecuteSql(MigrationStatement migrationStatement, DbConnection connection, DbTransaction transaction, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatementsInternal(IEnumerable1 migrationStatements, DbConnection connection, DbTransaction transaction, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatementsWithinTransaction(IEnumerable1 migrationStatements, DbTransaction transaction, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatementsWithinNewTransaction(IEnumerable1 migrationStatements, DbConnection connection, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatementsInternal(IEnumerable1 migrationStatements, DbConnection connection, DbInterceptionContext interceptionContext) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatementsInternal(IEnumerable1 migrationStatements, DbConnection connection) at System.Data.Entity.Migrations.DbMigrator.<>c__DisplayClass32.<ExecuteStatements>b__30() at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.<>c__DisplayClass1.<Execute>b__0() at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func1 operation) at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute(Action operation) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatements(IEnumerable1 migrationStatements, DbTransaction existingTransaction) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatements(IEnumerable1 migrationStatements) at System.Data.Entity.Migrations.Infrastructure.MigratorBase.ExecuteStatements(IEnumerable1 migrationStatements) at System.Data.Entity.Migrations.DbMigrator.ExecuteOperations(String migrationId, VersionedModel targetModel, IEnumerable1 operations, IEnumerable1 systemOperations, Boolean downgrading, Boolean auto) at System.Data.Entity.Migrations.DbMigrator.ApplyMigration(DbMigration migration, DbMigration lastMigration) at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.ApplyMigration(DbMigration migration, DbMigration lastMigration) at System.Data.Entity.Migrations.DbMigrator.Upgrade(IEnumerable1 pendingMigrations, String targetMigrationId, String lastMigrationId) at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId) at System.Data.Entity.Migrations.DbMigrator.UpdateInternal(String targetMigration) at System.Data.Entity.Migrations.DbMigrator.<>c__DisplayClasse.b__d() at System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase) at System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists(Action mustSucceedToKeepDatabase) at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration) at System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update(String targetMigration) at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.RunCore() at System.Data.Entity.Migrations.Design.ToolingFacade.BaseRunner.Run() ClientConnectionId:8aa18649-614e-4be4-a46d-fb780984d59f Error Number:2744,State:2,Class:16 Multiple identity columns specified for table 'CustomerContracts'. Only one identity column per table is allowed.

Why would I be getting this error. As you can see, I am using only one key nor am I renaming it (it's a new table as I dropped the db). Any help be appreciated.

Here is my migration I deleted the folder after i deleted the db and yet its still putting info into up and down.

 public partial class firstmigration : DbMigration
    {
        public override void Up()
        {
            DropPrimaryKey("dbo.CustomerContracts");
            AddColumn("dbo.CustomerContracts", "ItemId", c => c.Int(nullable: false, identity: true));
            AddPrimaryKey("dbo.CustomerContracts", "ItemId");
            DropColumn("dbo.CustomerContracts", "TeamId");
        }

        public override void Down()
        {
            AddColumn("dbo.CustomerContracts", "TeamId", c => c.Int(nullable: false, identity: true));
            DropPrimaryKey("dbo.CustomerContracts");
            DropColumn("dbo.CustomerContracts", "ItemId");
            AddPrimaryKey("dbo.CustomerContracts", "TeamId");
        }
    }

Paul Michaels Paul Michaels · Accepted Answer · 2018-04-26T09:13:38

Try this:

public override void Up()
{
    DropPrimaryKey("dbo.CustomerContracts");
    DropColumn("dbo.CustomerContracts", "TeamId"); // Drop this first
    AddColumn("dbo.CustomerContracts", "ItemId", c => c.Int(nullable: false, identity: true));
    AddPrimaryKey("dbo.CustomerContracts", "ItemId");
}

Cannot create Multiple Ids but yet I only have one

1 Answers