Python列表生成式应用方式

In [1]: import MySQLdb as mysql

In [2]: conn=mysql.connect(user='root',host='127.0.0.1',passwd='123456',db='lyz',charset='utf8')

In [3]: conn.autocommit(True)

In [4]: cur = conn.cursor()

In [5]: info = ['id','name','name_cn','email','mobile']

In [6]: sql = 'select %s from users'%','.join(info)

In [7]: sql
Out[7]: 'select id,name,name_cn,email,mobile from users'

In [8]: cur.execute(sql)
Out[8]: 2L

In [9]: res = cur.fetchall()  # fetchall()获得的是个嵌套的元组

In [10]: res
Out[10]:
((1L,
  u'liuyongzhan',
  u'\u5218\u6c38\u6808',
  u'1665439369@qq.com',
  u'2147483647'),
 (6L, u'lyz', u'1111', u'1111', u'1111'))

In [11]: ha = [dict((k,row[i]) for i,k in enumerate(info)) for row in res]

In [12]: ha
Out[12]:
[{'email': u'1665439369@qq.com',
  'id': 1L,
  'mobile': u'2147483647',
  'name': u'liuyongzhan',
  'name_cn': u'\u5218\u6c38\u6808'},
 {'email': u'1111',
  'id': 6L,
  'mobile': u'1111',
  'name': u'lyz',
  'name_cn': u'1111'}]

data = dict(request.form)  # 或者前端直接以json格式传过来，就可以写成data=request.get_json()
ZiChan = ['hostname','cpu','mem','exdate','author','note']
sql='insert into zichan (%s) values (%s)'%(','.join(ZiChan),','.join(['"%s"'%data[x][0] for x in ZiChan]))

data = {'name':'lyz','age':26,'mobile':15768216871,'email':'1665439369@qq.com'}
key,values = [],[]                                                       
for k,v in data.items():                                                       
    key.append(k)
    values.append('"%s"'%v)
sql = 'insert into users (%s) values (%s)'%(','.join(key),','.join(values))
执行结果：
'insert into users (mobile,age,name,email) values ("15768216871","26","lyz","1665439369@qq.com")'

ida = request.form.get('id')
hostname = request.form.get('hostname')
cpu = request.form.get('cpu')
mem = request.form.get('mem')
exdate = request.form.get('exdate')
author = request.form.get('author')
note = request.form.get('note')
sql = 'update zichan set hostname ="%s",cpu ="%s",mem ="%s",exdate ="%s",author ="%s",note ="%s" where id=%s'%(hostname,cpu,mem,exdate,author,note,ida)

data = dict(request.form)
ida = data.get('id',None)[0]
ZiChan = ['hostname','cpu','mem','exdate','author','note']
arr = ["%s='%s'" %(k,data[k][0]) for k in ZiChan]
sql = 'update zichan set %s where id=%s'%(','.join(arr),ida)

data = request.get_json()
ida = data.get('id',None)
data = data.get('data',None)
arr = ["%s='%s'"%(k,data[k] for k in data)]   # 结果为：["'hostname‘='xxx‘","'cpu‘='xxx‘",......]
sql = 'update zichan set %s where id=%s'%(','.join(arr),ida)