Python连接MySql数据库

Python连接MySql数据库

连接数据库

1.安装pymsql：

pip install pymysql

2.建立数据库连接文件dbBase.py，编辑文件内容：

import pymysql
class DBConnect:
    def db_connect(DATABASE_URL):
        conn = pymysql.connect(host=host, port=port, user=user, passwd=password, db=db, charset=charset)
        cursor = conn.cursor()

3.执行SQL查询：

# create table
sql = "create table if not exists mobile(name varchar(128) primary key, moblie_id varchar(128), moblie_name varchar(128), moblie_price varchar(128))"
cursor.execute(sql)

# Insert one record
sql = "insert into user(name, password) values ('%s', %s)" % ("张三", "bb")
try:
    cursor.execute(sql)
    conn.commit()
except Exception as e:
    print(e)

# Insert a number of records
sql = "insert into user(name, moblie_id) values (%s, %s)"
val = (("李四", "cc"), ("王五", "dd"), ("洪六", "ee"))
try:
    cursor.executemany(sql, val)
    conn.commit()
except Exception as e:
    print(e)

# Database query
sql = "select * from mobile"
try:
    cursor.execute(sql)
    conn.commit()
except Exception as e:
    print(e)

# Database delete
sql = "delete from "tablename" where "columnname" OPERATOR "value" [and|or "column" OPERATOR "value"]"
try:
    cursor.execute(sql)
    conn.commit()
except Exception as e:
    print(e)

# Database update
sql = "update t_test t  set t.password = '***'  where t.bs = 2"
try:
    cursor.execute(sql)
    conn.commit()
except Exception as e:
    print(e)

指定读取数据库结果的数据类型：

MySql数据库默认的读取结果是一个元祖，有时候操作元祖并不符合业务需求，这个时候需要指定一下输出的数据类型， 方法有2种：

第一种【在连接数据库语句中设置数据库游标数据类型】

conn = pymysql.connect(host=host, port=port, user=user, passwd=password, db=dbname, charset=charset,
cursorclass=pymysql.cursors.DictCursor)

第二种【在获取游标的时候指定数据库游标的数据类型】

cursor = conn.cursor(pymysql.cursors.DictCursor)