/// <summary>
/// 获取所有列 逗号分隔 mysql用``,sqlserver用[]
/// </summary>
/// <param name="prefix">如A 最终sql语句就是A.Id，可为空</param>
/// <returns></returns>
public string GetAllColumns <T>(string prefix = "") where T : BaseEntity
{
return(SQLBuilderHelper.GetAllColumns(typeof(T), this.GetORMDBType(), prefix));
}