【python-sql】sql操作时遇到的坑

针对python的sql语句的封装以及调用:

python的db操作类:

# -*- coding: utf-8 -*-
# coding=utf-8 import MySQLdb class Database(object): [_db_handler, _cursor] = (None, None)
def __init__(self, host=HOST, port=PORT, user='user', passwd='passwd', db_name='mydb'):
try:
self._db_handler = MySQLdb.connect(host, user, passwd, db_name)
self._cursor = self._db_handler.cursor()
except Exception, e:
print e def query(self, table, condition=None, column='*',log=""):
try:
cmd = 'SELECT %s from %s ' % (column, table)
if condition:
cmd = cmd + "WHERE %s" % condition
cmd = cmd + ';'
log.info(cmd)
self._cursor.execute('set NAMES utf8')
self._cursor.execute(cmd)
resultset = self._cursor.fetchall()
rowcount = self._cursor.rowcount
return [resultset, rowcount]
except:
log.error("Error: unable to fecth data") def execute(self, command, parameters,log):
try:
cmd = command % parameters
cmd = cmd + ';'
log.info(cmd)
self._cursor.execute('set NAMES utf8')
rowcount = self._cursor.execute(cmd)
self._db_handler.commit()
return rowcount
except Exception, e:
log.error('error:%s' % str(e))
log.error('execute db error,rollback')
self._cursor.rollback() def batchMysqlOpr(self, sqldata, rsdb):
try:
for item in range(len(sqldata)):
rs = self.query(sqldata[item][1], sqldata[item][2], column=sqldata[item][3])
rsdb.setdefault(sqldata[item][0], rs)
except Exception, e:
print e
return def singleMysqlOpr(self,key,command,paramters,rsdb):
try:
rowcount = self.execute(command, paramters)
if key:
rsdb.setdefault(key, rowcount)
return rowcount
except Exception, e:
print e
return if __name__ == '__main__':
pass

通过以上代码进行具体操作的时候,比如insert操作,如果我的表中第一个字段是自增的,需要insert into biao(ziduan1, ziduan2, ziduan3) values(value1, value2, value3) ,把具体字段写清楚,而不能直接通过insert into biao values(ziduan1, ziduan2, ziduan3)的这种方式来调用

并且,在调用的时候,如果插入的内容是string类型的,则sql的命令需要按照:

sql_command = 'insert into a (ziduan1, ziduan2, ziduan3) values("%s", "%s", "%s")'

#注意sql的命令行语句本身就是str型的,通过''括起来的,values里面的%s就需要通过""双引号括起来,如果外面是双引号,则里面的%s就写成单引号,能区分开就可以

parameters = (string_bianliang1, stringbianliang2, string_bianliang3)

之后进行db.execute(sql_command, paramters),才可以正常运行

这里已经踩过坑了,一定要注意~~~

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