1.创建列

alter table tablename add colname type not null default '0';
例：
alter table mmanapp_mmanmedia add appid_id integer not null default 372;

2.删除列

alter table tablename drop column colname;
例：
alter table mmanapp_mmanmedia drop column appid_id;

3.在已经存在的列上创建外键关联

ALTER TABLE yourtablename    ADD [CONSTRAINT symbol] FOREIGN KEY [id] (index_col_name, ...)    REFERENCES tbl_name (index_col_name, ...)    [ON DELETE ...

最近对django真是大爱呀，哈哈。公司有个需求是为一些素材动态生成属性字段，所以需要django来动态生成表单。

一开始的写法如下：

class AddObjForm(forms.Form):
    id = forms.CharField()
    def __init__(self, *args, **kwargs):
        mdfields = copy.deepcopy(kwargs['mdfields'])
        del kwargs['mdfields']
        super(AddObjForm, self).__init__(*args, **kwargs)
        if mdfields is not None:
            for f in mdfields:
                exestr = ""
                if f.showtype == 0:
                    exestr = 'self.'+f.name+"=forms.CharField()"
                else:
                    exestr = 'self.'+f ...