variab 2020-06-14
1.mysql操作
import pymysql from DBUtils.PooledDB import PooledDB class SQLHandler(object): def __init__(self, host, port, db_username, db_password, db_name): # pip install --default-timeout=100 dbutils self.pool = PooledDB( # 使用链接数据库的模块import pymysql creator=pymysql, # 连接池允许的最大连接数,0和None表示不限制连接数 maxconnections=6, # 初始化时,链接池中至少创建的空闲的链接,0表示不创建 mincached=2, # 链接池中最多闲置的链接,0和None不限制 maxcached=5, # 链接池中最多共享的链接数量,0和None表示全部共享。 # 因为pymysql和MySQLdb等模块的 threadsafety都为1, # 所有值无论设置为多少,maxcached永远为0,所以永远是所有链接都共享。 maxshared=3, # 连接池中如果没有可用连接后,是否阻塞等待。True,等待;False,不等待然后报错 blocking=True, # 一个链接最多被重复使用的次数,None表示无限制 maxusage=None, # 开始会话前执行的命令列表。如:["set datestyle to ...", "set time zone ..."] setsession=[], # ping MySQL服务端,检查是否服务可用。 # 如:0 = None = never, 1 = default = whenever it is requested, # 2 = when a cursor is created, 4 = when a query is executed, 7 = always ping=0, # 数据库信息 host=host, port=int(port), user=db_username, password=db_password, database=db_name, charset=‘utf8‘ ) def create_conn_cursor(self): # 创建连接 conn = self.pool.connection() # 创建游标 cursor = conn.cursor(pymysql.cursors.DictCursor) # 返回conn, cursor return conn, cursor def fetch_one(self, sql, args): conn, cursor = self.create_conn_cursor() cursor.execute(sql, args) result = cursor.fetchone() cursor.close() conn.close() return result def fetch_many(self, sql, args): conn, cursor = self.create_conn_cursor() cursor.execute(sql) result = cursor.fetchmany(args) cursor.close() conn.close() return result def fetch_all(self, sql, args): conn, cursor = self.create_conn_cursor() cursor.execute(sql, args) result = cursor.fetchall() cursor.close() conn.close() return result def insert_one(self, sql, args): conn, cursor = self.create_conn_cursor() res = cursor.execute(sql, args) conn.commit() print(res) conn.close() return res def insert_many(self, sql, args): conn, cursor = self.create_conn_cursor() res = cursor.executemany(sql, args) conn.commit() print(res) conn.close() return res def update(self, sql, args): conn, cursor = self.create_conn_cursor() res = cursor.execute(sql, args) conn.commit() print(res) conn.close() return res def delete(self, sql, args): conn, cursor = self.create_conn_cursor() res = cursor.execute(sql, args) conn.commit() print(res) conn.close() return res
test测试
from SQLHandler import SQLHandler if __name__ == ‘__main__‘: # 连接mysql sqlhelper = SQLHandler("192.168.1.6", 3306, "root", "root", "datatest") ## 查询 # 指定列名查询 # ret = sqlhelper.fetch_all("select * from user where id=%s",(2)) # ret = sqlhelper.fetch_all("select * from user where name=%s",(‘apollo‘)) # 显示查询结果第一条 # ret = sqlhelper.fetch_one("select * from user",None) # 显示查询结果前两条 # ret = sqlhelper.fetch_many("select * from user",(2)) # 显示查询结果全部 # ret = sqlhelper.fetch_all("select * from user", None) # for (index, item) in enumerate(ret, 1): # print(index, item) ## 插入 # 插入一条数据 # 方式1: # ret = sqlhelper.insert_one("insert into user VALUES (%s,%s,%s)",(10,"litch",56)) # 方式2: # ret = sqlhelper.insert_one("insert into user (name,age)VALUES (%s,%s)",("banana",12)) # 插入多条数据 data = [] for index in range(0,100000): by = str(index) name = "name2"+by temp = (name,0,16) data.append(temp) sql = ‘insert into user(name,six,age) values(%s,%s,%s);‘ ret = sqlhelper.insert_many(sql,data) ## 更新 # ret = sqlhelper.update("update user SET name=%s WHERE id=%s",("Smith",1)) ## 删除 # ret = sqlhelper.delete("delete from user where name=%s;",[("jack88")]) print(ret)