private void RemoveTable(Table table)
        {
            if ((Context.RunDataLossOperation & DataLossOperation.DropTable) != 0)
            {
                Context.NotifyDataLoss("删除表");

                foreach (var column in table.FindNormalColumns())
                {
                    this.RemoveColumn(column);
                }

                this.AddOperation(new DropTable
                {
                    CopyFromTable = table
                });
            }
        }
        private void AddTable(Table table)
        {
            var op = new CreateTable()
            {
                CopyFromTable = table
            };
            this.AddOperation(op);

            foreach (var column in table.FindNormalColumns())
            {
                this.AddColumn(column);
            }
        }