1. Install pymysql

Enter import pymysql in Pycharm, click Install according to the prompt, and the module will be installed to the lib directory of the default Python installation directory. The following is the path of the pymysql module I installed.

or use pip

Two, connect to the database

Use the connect function to create a connection object. This connection object provides operations such as closing the database and transaction rollback. The
general parameters are: host, user, password, port (default is 3306), database (the name of the database you want to connect to)

connect() method parameters

Parameter Description:

parameter	illustrate
host=	Database connection address
user=	database username
password=	database password
database=	The name of the database to connect to
port=3306	Connection port, default 3306
charset=utf8	Set the character set, usually utf8
connect_timeout=10	The connection database timeout time, generally defaults to 10 seconds
dsn	Data source name, given this parameter indicates database dependency
max_allowed_packet	16 * 1024 * 1024
autocommit	False autocommit defaults to false

Common methods for connecting objects :

method name	illustrate
cursor()	Get the cursor object, operate the database, such as performing DML operations, calling stored procedures, etc.
commit()	commit transaction
rollback()	rollback transaction
close()	close database connection

Common methods of cursor cursor objects

method name	illustrate
execute(query)	Execute database operations, such as sql statements or database commands
executemany(query,params)	For batch operations, such as: batch update
fetchone()	Get the next record in the query result set
fetchmany(size)	Get the specified number of records in the query result set, size defaults to 1
fetchall()	Get all records in the query result set
nextset()	Skip to the next available result set
close()	close the current cursor object

3. Database operation

3.1 Query

import pymysql
# 创建数据库连接对象
db = pymysql.connect(host="192.168.2.211",
                     user="root",
                     password="winner@001",
                     database="ipvacloud",
                     charset="utf8")
# 创建一个新游标来执行查询
curses = db.cursor()

siteId = "Ahczlcc_P00001"

# 查询SQL
selectSQL = """
    SELECT SiteId,SiteName from  site_all_info where SiteId ='%s'; 
""" % siteId
try:
    # 执行sql语句，也可执行数据库命令
    curses.execute(selectSQL)
    # 所有结果
    result = curses.fetchall()
    print(type(result))
    print(result)

except Exception as e:
    db.rollback()     # 回滚
    print("查询失败", e)
finally:
    curses.close()    # 关闭当前游标
    db.close()        # 关闭数据库连接

search result:

Additions, deletions, and changes require the operation of submitting transactions, and queries do not need to submit transactions. However, if you loop the query, you must submit the transaction, otherwise the results will be duplicated.

3.2 update

import pymysql
# 创建数据库连接对象
db = pymysql.connect(host="192.168.2.211",
                     user="root",
                     password="winner@001",
                     database="ipvacloud",
                     charset="utf8")
# 创建一个新游标来执行查询
curses = db.cursor()

siteId = "Ahczlcc_P00001"
siteName = "大中国安徽滁州乐彩城"

# 查询SQL
selectSQL = """
    update  site_all_info set sitename = '%s' where SiteId ='%s'; 
""" % (siteName, siteId)
try:
    # 执行sql语句，也可执行数据库命令
    curses.execute(selectSQL)
    # 增删改，必须执行事务
    db.commit()
    # 所有结果
    result = curses.fetchall()
    print(type(result))
    print(result)

except Exception as e:
    db.rollback()     # 回滚
    print("查询失败", e)
finally:
    curses.close()    # 关闭当前游标
    db.close()        # 关闭数据库连接

Query whether the update is successful

3.3 Batch update using loop

import pymysql

# 创建数据库连接对象
db = pymysql.connect(host="192.168.2.211",
                     user="root",
                     password="winner@001",
                     database="ipvacloud",
                     charset="utf8")
# 创建一个新游标来执行查询
curses = db.cursor()

siteId = "Ahczlcc_P00001"
siteName = "大中国安徽滁州乐彩城"

table_name = "site_all_info"
update_list = ['Ahczlcc_P00001S00004', 'Ahczlcc_P00001S00005']
update_condition_list = ['北餐饮门', '北大门']

for i in range(len(update_list)):
    # 查询SQL
    selectSQL = """
        update  %s set sitename = '%s' where SiteId ='%s'; 
    """ % (table_name, update_condition_list[i], update_list[i])
    print(table_name, update_condition_list[i], update_list[i])

    try:
        # 执行sql语句
        curses.execute(selectSQL)
        # 执行事务
        db.commit()
    except Exception as e:
        db.rollback()
        print(e)
curses.close()
db.close()

Comparison of execution results: