一、安装
pip install pymysql
二、连接数据库
- 三种连接数据库的方式
import pymysql
# 方式一
conn = pymysql.connect('localhost', 'root', 'root')
# 方式二
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='root', db='', charset='utf8')
# 方式三
config = {
'host': '127.0.0.1',
'port': 3306,
'user': 'root',
'passwd': 'root',
'charset': 'utf8'
}
conn = pymysql.connect(**config)三、创建数据库
- 创建一个test数据库并进入
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
# 使用 cursor() 方法创建一个游标对象 cursor
cursor = db.cursor()
cursor.execute('DROP DATABASE IF EXISTS test')
cursor.execute('CREATE DATABASE IF NOT EXISTS test')
conn.select_db('test')四、创建数据表
- 创建一张user表
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
cursor.execute('CREATE TABLE user(id int primary key,name varchar(30))')五、插入一条数据
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
try:
# 执行SQL语句
sql = 'INSERT INTO user values("%d","%s")' %(1,"autofelix")
cursor.execute(sql)
# 提交到数据库执行
db.commit()
except:
# 发生错误时回滚
db.rollback()
finally:
# 关闭游标连接
cursor.close()
# 关闭数据库连接
conn.close()六、插入多条数据
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
try:
# 执行SQL语句
values = [(1, 'autofelix'), (2, '飞兔小哥')]
cursor.executemany('INSERT INTO user values(%s,%s)', values)
# 提交到数据库执行
db.commit()
except:
# 发生错误时回滚
db.rollback()
finally:
# 关闭游标连接
cursor.close()
# 关闭数据库连接
conn.close()七、数据统计
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
count = cursor.execute('SELECT * FROM user')
# 统计数据总数
print('total records: %d' %count)
# 统计字段数
print('total records:', cursor.rowcount)八、获取表名信息
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
desc = cursor.description
print("%s %3s" % (desc[0][0], desc[1][0]))九、获取单条数据
- 使用 fetchone 方法获取单条数据
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
# 使用 execute() 方法执行 SQL 查询
cursor.execute("SELECT VERSION()")
# 使用 fetchone() 方法获取单条数据.
data = cursor.fetchone()
print("Database version : %s " % data)
# 关闭数据库连接
db.close()十、查询多条数据
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
cursor.execute('SELECT * FROM user')
results = cursor.fetchmany(5)
for r in results:
print (r)十一、查询所有数据
import pymysql
db = pymysql.connect("localhost", "root", "root", "test")
cursor = db.cursor()
cursor.execute('SELECT * FROM user')
results = cursor.fetchall()
for r in results:
print (r)十二、上下文管理
- 每次都连接关闭很麻烦，使用上下文管理，简化连接过程
import pymysql
import contextlib
# 定义上下文管理器，连接后自动关闭连接
@contextlib.contextmanager
def mysql(host='127.0.0.1', port=3306, user='root', passwd='', db='test',charset='utf8'):
conn = pymysql.connect(host=host, port=port, user=user, passwd=passwd, db=db, charset=charset)
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
try:
yield cursor
finally:
conn.commit()
cursor.close()
conn.close()
# 执行sql
with mysql() as cursor:
print(cursor)
count = cursor.execute("select * from user")
row_1 = cursor.fetchone()
print row_count, row_1到此这篇关于python 包 pymysql 数据库操作方法的文章就介绍到这了,更多相关 pymysql 数据库操作 内容请搜索Devmax以前的文章或继续浏览下面的相关文章希望大家以后多多支持Devmax！