pymysql 对数据库进行增删查改

Pymysql 是 Python 语言下操作 MySQL 数据库的库，可以通过它来进行增删查改等操作。

以下是针对 pymysql 进行增删查改的示例代码：

1. 建立连接

import pymysql

conn = pymysql.connect(host='localhost', user='root', password='password', database='test')

2. 插入数据

cursor = conn.cursor()

sql = "INSERT INTO table_name (column1, column2, column3) VALUES (%s, %s, %s)"
val = ("value1", "value2", "value3")

cursor.execute(sql, val)
conn.commit()

3. 查询数据

cursor = conn.cursor()

sql = "SELECT * FROM table_name WHERE column1 = %s"
val = ("value1", )

cursor.execute(sql, val)

result = cursor.fetchall()

for row in result:
    print(row)

4. 更新数据

cursor = conn.cursor()

sql = "UPDATE table_name SET column1 = %s WHERE column2 = %s"
val = ("new_value1", "value2")

cursor.execute(sql, val)
conn.commit()

5. 删除数据

cursor = conn.cursor()

sql = "DELETE FROM table_name WHERE column1 = %s"
val = ("value1", )

cursor.execute(sql, val)
conn.commit()

注意：在使用完 pymysql 后需要关闭连接，以释放资源。

conn.close()