python实现增删改查

python连接数据库

# 连接数据库
def connection():
    try:
        db=pymysql.Connection(host='localhost',user='root',password='20214063',database='aa')
        print("数据库连接成功！")
    except pymysql.err as e:
        print("数据库连接失败"+str(e))
    finally:
        db.close()

python查询

# 执行查询数据操作
def check():
    db=pymysql.Connection(host='localhost',user='root',password='20214063',database='aa')
    cur=db.cursor()
    sqlQuery="select * from person"
    try:
        cur.execute(sqlQuery)
        result=cur.fetchall()
        for row in result:
            print(f"id：{row[0]}  name:{row[1]}  age:{row[2]}   birth:{row[3]}")
    except pymysql.Error as e:
        print("查询失败！"+str(e))
        db.rollback()
    finally:
        db.close()

python添加数据

# 执行添加数据操作
def add():
    db=pymysql.Connection(host='localhost',user='root',password='20214063',database='aa')
    cur=db.cursor()
    sqlQuery="insert into person(id,name,age,birth) values(%s,%s,%s,%s)"
    value=(23,"小刘",12,"2023-05-21")
    try:
        cur.execute(sqlQuery,value)
        db.commit()
        print("数据添加成功！")
    except pymysql.Error as e:
        print("数据添加失败！"+str(e))
        db.rollback()
    finally:
        db.close()

python修改数据

# 执行修改操作
def update():
    db=pymysql.Connection(host='localhost',user='root',password='20214063',database='aa')
    cur=db.cursor()
    sqlQuery="update person set birth=%s where id=%s"
    birth="2023-05-22"
    id=23
    value=birth,id
    try:
        cur.execute(sqlQuery,value)
        db.commit()
        print("数据修改成功！")
    except pymysql.Error as e:
        print("数据修改失败！"+str(e))
        db.rollback()
    finally:
        db.close()

python删除数据

# 执行删除操作
def delete():
    db=pymysql.Connection(host='localhost',user='root',password='20214063',database='aa')
    cur=db.cursor()
    sqlQuery="delete from person where id=%s"
    id=23
    value=id
    try:
        cur.execute(sqlQuery,value)
        db.commit()
        print("数据删除成功！")
    except pymysql.Error as e:
        print("数据删除失败！"+str(e))
        db.rollback()
    finally:
        db.close()