if (not exists (select name from syscolumns where id = object_id('Pub_AgentServer') and name = 'FactoryType'))   
    Begin

    ALTER TABLE Pub_AgentServer ADD
    FactoryType int default(0) not null

    EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'转发版本
type:radio
enum:{内部版本=0,开放版本=1}
default:0
tooltip:标识当前转发版本
' ,@level0type=N'SCHEMA', @level0name=N'dbo', @level1type=N'TABLE', @level1name=N'Pub_AgentServer', @level2type=N'COLUMN', @level2name=N'FactoryType'

    End