漫漫长夜,最近python2转python3之后,发现自己还没有手写过mysql连接的工具类,发现稍微改改之前python2的版本在python3就可用直接使用。下面就废话少说,直接上代码。
使用pip3安装pymysql
pip3 install pymysql
工具类代码
# -*- coding: utf-8 -*-
import pymysql
import re
class MysqldbHelper(object): # 继承object类所有方法
'''
构造方法:
config = {
'host': '127.0.0.1',
'port': 3306,
'user': 'root',
'passwd': 'root',
'charset':'utf8',
'cursorclass':pymysql.cursors.DictCursor
}
conn = pymysql.connect(**config)
conn.autocommit(1)
cursor = conn.cursor()
'''
def __init__(self , config):
self.host = config['host']
self.username = config['user']
self.password = config['passwd']
self.port = config['port']
self.con = None
self.cur = None
try:
self.con = pymysql.connect(**config)
self.con.autocommit(1)
# 所有的查询,都在连接 con 的一个模块 cursor 上面运行的
self.cur = self.con.cursor()
except:
print("DataBase connect error,please check the db config.")
# 关闭数据库连接
def close(self):
if not self.con:
self.con.close()
else:
print("DataBase doesn't connect,close connectiong error;please check the db config.")
# 创建数据库
def createDataBase(self,DB_NAME):
# 创建数据库
self.cur.execute('CREATE DATABASE IF NOT EXISTS %s DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci' % DB_NAME)
self.con.select_db(DB_NAME)
print('creatDatabase:' + DB_NAME)
# 选择数据库
def selectDataBase(self,DB_NAME):
self.con.select_db(DB_NAME)
# 获取数据库版本号
def getVersion(self):
self.cur.execute("SELECT VERSION()")
return self.getOneData()
# 获取上个查询的结果
def getOneData(self):
# 取得上个查询的结果,是单个结果
data = self.cur.fetchone()
return data
# 创建数据库表
def creatTable(self, tablename, attrdict, constraint):
"""创建数据库表
args:
tablename :表名字
attrdict :属性键值对,{'book_name':'varchar(200) NOT NULL'...}
constraint :主外键约束,PRIMARY KEY(`id`)
"""
if self.isExistTable(tablename):
print("%s is exit" % tablename)
return
sql = ''
sql_mid = '`id` bigint(11) NOT NULL AUTO_INCREMENT,'
for attr,value in attrdict.items():
sql_mid = sql_mid + '`'+attr + '`'+' '+ value+','
sql = sql + 'CREATE TABLE IF NOT EXISTS %s ('%tablename
sql = sql + sql_mid
sql = sql + constraint
sql = sql + ') ENGINE=InnoDB DEFAULT CHARSET=utf8'
print('creatTable:'+sql)
self.executeCommit(sql)
def executeSql(self,sql=''):
"""执行sql语句,针对读操作返回结果集
args:
sql :sql语句
"""
try:
self.cur.execute(sql)
records = self.cur.fetchall()
return records
except pymysql.Error as e:
error = 'MySQL execute failed! ERROR (%s): %s' %(e.args[0],e.args[1])
print(error)
def executeCommit(self,sql=''):
"""执行数据库sql语句,针对更新,删除,事务等操作失败时回滚
"""
try:
self.cur.execute(sql)
self.con.commit()
except pymysql.Error as e:
self.con.rollback()
error = 'MySQL execute failed! ERROR (%s): %s' %(e.args[0],e.args[1])
print("error:", error)
return error
def insert(self, tablename, params):
"""创建数据库表
args:
tablename :表名字
key :属性键
value :属性值
"""
key = []
value = []
for tmpkey, tmpvalue in params.items():
key.append(tmpkey)
if isinstance(tmpvalue, str):
value.append("\'" + tmpvalue + "\'")
else:
value.append(tmpvalue)
attrs_sql = '('+','.join(key)+')'
values_sql = ' values('+','.join(value)+')'
sql = 'insert into %s'%tablename
sql = sql + attrs_sql + values_sql
print('_insert:'+sql)
self.executeCommit(sql)
def select(self, tablename, cond_dict='', order='', fields='*'):
"""查询数据
args:
tablename :表名字
cond_dict :查询条件
order :排序条件
example:
print mydb.select(table)
print mydb.select(table, fields=["name"])
print mydb.select(table, fields=["name", "age"])
print mydb.select(table, fields=["age", "name"])
"""
consql = ' '
if cond_dict!='':
for k, v in cond_dict.items():
consql = consql+'`'+k +'`'+ '=' + '"'+v + '"' + ' and'
consql = consql + ' 1=1 '
if fields == "*":
sql = 'select * from %s where ' % tablename
else:
if isinstance(fields, list):
fields = ",".join(fields)
sql = 'select %s from %s where ' % (fields, tablename)
else:
print("fields input error, please input list fields.")
sql = sql + consql + order
print('select:' + sql)
return self.executeSql(sql)
def insertMany(self,table, attrs, values):
"""插入多条数据
args:
tablename :表名字
attrs :属性键
values :属性值
example:
table='test_mysqldb'
key = ["id" ,"name", "age"]
value = [[101, "liuqiao", "25"], [102,"liuqiao1", "26"], [103 ,"liuqiao2", "27"], [104 ,"liuqiao3", "28"]]
mydb.insertMany(table, key, value)
"""
values_sql = ['%s' for v in attrs]
attrs_sql = '('+','.join(attrs)+')'
values_sql = ' values('+','.join(values_sql)+')'
sql = 'insert into %s'% table
sql = sql + attrs_sql + values_sql
print('insertMany:'+sql)
try:
print(sql)
for i in range(0,len(values),20000):
self.cur.executemany(sql,values[i:i+20000])
self.con.commit()
except pymysql.Error as e:
self.con.rollback()
error = 'insertMany executemany failed! ERROR (%s): %s' %(e.args[0],e.args[1])
print(error)
def delete(self, tablename, cond_dict):
"""删除数据
args:
tablename :表名字
cond_dict :删除条件字典
example:
params = {"name" : "caixinglong", "age" : "38"}
mydb.delete(table, params)
"""
consql = ' '
if cond_dict!='':
for k, v in cond_dict.items():
if isinstance(v, str):
v = "\'" + v + "\'"
consql = consql + tablename + "." + k + '=' + v + ' and '
consql = consql + ' 1=1 '
sql = "DELETE FROM %s where%s" % (tablename, consql)
print(sql)
return self.executeCommit(sql)
def update(self, tablename, attrs_dict, cond_dict):
"""更新数据
args:
tablename :表名字
attrs_dict :更新属性键值对字典
cond_dict :更新条件字典
example:
params = {"name" : "caixinglong", "age" : "38"}
cond_dict = {"name" : "liuqiao", "age" : "18"}
mydb.update(table, params, cond_dict)
"""
attrs_list = []
consql = ' '
for tmpkey, tmpvalue in attrs_dict.items():
attrs_list.append("`" + tmpkey + "`" + "=" +"\'" + tmpvalue + "\'")
attrs_sql = ",".join(attrs_list)
print("attrs_sql:", attrs_sql)
if cond_dict!='':
for k, v in cond_dict.items():
if isinstance(v, str):
v = "\'" + v + "\'"
consql = consql + "`" + tablename +"`." + "`" + k + "`" + '=' + v + ' and '
consql = consql + ' 1=1 '
sql = "UPDATE %s SET %s where%s" % (tablename, attrs_sql, consql)
print(sql)
return self.executeCommit(sql)
def dropTable(self, tablename):
"""删除数据库表
args:
tablename :表名字
"""
sql = "DROP TABLE %s" % tablename
self.executeCommit(sql)
def deleteTable(self, tablename):
"""清空数据库表
args:
tablename :表名字
"""
sql = "DELETE FROM %s" % tablename
print("sql=",sql)
self.executeCommit(sql)
def isExistTable(self, tablename):
"""判断数据表是否存在
args:
tablename :表名字
Return:
存在返回True,不存在返回False
"""
sql = "select * from %s" % tablename
result = self.executeCommit(sql)
if result is None:
return True
else:
if re.search("doesn't exist", result):
return False
else:
return True
if __name__ == "__main__":
# 定义数据库访问参数
config = {
'host': '127.0.0.1',
'port': 6806,
'user': 'root',
'passwd': 'tcltest',
'charset': 'utf8',
'cursorclass': pymysql.cursors.DictCursor
}
# 初始化打开数据库连接
mydb = MysqldbHelper(config)
# 打印数据库版本
print(mydb.getVersion())
# 创建数据库
DB_NAME = 'test_db'
# mydb.createDataBase(DB_NAME)
# 选择数据库
print("========= 选择数据库%s ===========" % DB_NAME)
mydb.selectDataBase(DB_NAME)
#创建表
TABLE_NAME = 'test_user'
print("========= 选择数据表%s ===========" % TABLE_NAME)
# CREATE TABLE %s(id int(11) primary key,name varchar(30))' %TABLE_NAME
attrdict = {'name':'varchar(30) NOT NULL'}
constraint = "PRIMARY KEY(`id`)"
# mydb.creatTable(TABLE_NAME,attrdict,constraint)
# 插入纪录
print("========= 单条数据插入 ===========")
params = {}
for i in range(5):
params.update({"name":"testuser"+str(i)}) # 生成字典数据,循环插入
print(params)
mydb.insert(TABLE_NAME, params)
print("")
# 批量插入数据
print("========= 多条数据同时插入 ===========")
insert_values = []
for i in range(5):
# values.append((i,"testuser"+str(i)))
insert_values.append([u"测试用户"+str(i)]) # 插入中文数据
print(insert_values)
insert_attrs = ["name"]
mydb.insertMany(TABLE_NAME,insert_attrs, insert_values)
# 数据查询
print("========= 数据查询 ===========")
print(mydb.select(TABLE_NAME, fields=["id", "name"]))
print(mydb.select(TABLE_NAME, cond_dict = {'name':'测试用户2'},fields=["id", "name"]))
print(mydb.select(TABLE_NAME, cond_dict = {'name':'测试用户2'},fields=["id", "name"],order="order by id desc"))
# 删除数据
print("========= 删除数据 ===========")
delete_params = {"name": "测试用户2"}
mydb.delete(TABLE_NAME, delete_params)
# 更新数据
print("========= 更新数据 ===========")
update_params = {"name": "测试用户99"} # 需要更新为什么值
update_cond_dict = {"name": "测试用户3"} # 更新执行的查询条件
mydb.update(TABLE_NAME, update_params, update_cond_dict)
# 删除表数据
print("========= 删除表数据 ===========")
mydb.deleteTable(TABLE_NAME)
# 删除表
print("========= 删除表 ===========")
mydb.dropTable(TABLE_NAME)
![](http://img.e-com-net.com/image/info10/08c9cce08bef4b4e86ff7de96afae5ae.jpg)