python连接mysql的一些基础知识＋安装Navicat可视化数据库+flask

一．mysql基础知识

１．connect连接数据库

import pymysqldef get_conn():conn = pymysql.connect(host='xxx.xxx.xxx.xxx', port=3306, user='root', passwd='', db='newspaper_rest') # db:表示数据库名称return conn

２．创建表

import pymysqldef get_conn():conn = pymysql.connect(host='xxx.xxx.xxx.xxx', port=3306, user='root', passwd='', db='newspaper_rest') # db:表示数据库名称return conn# 创建mysql表
def ceartTable(cursor,form_name):#删数据库行为　要慎重# # # 创建newspaper_rest 数据库, 如果存在则删除newspaper_rest 数据库cursor.execute("drop database if exists newspaper_rest")cursor.execute("create database newspaper_rest")# 选择 newspaper_rest 这个数据库cursor.execute("use newspaper_rest")# KEY# IDENTITY# 将sql中的内容为创建一个名为recordid_form的表sql = """CREATE TABLE IF NOT EXISTS %s (recordid VARCHAR (100),publish_date VARCHAR (100),page_num VARCHAR (100),ISdeal VARCHAR (1),primary key (recordid,publish_date,page_num))"""%(form_name)# # 如果存在表则删除# cursor.execute("drop table if exists %s"%(form_name))# 创建表cursor.execute(sql)print("successfully create table")db = get_conn()
cursor = db.cursor()# # # # # # 创建数据库和表
form_name = 'imgs_list_path_form'
ceartTable(cursor, form_name)

３．插入并且加上了重复插入的异常

# 在存放图片路径的表中插入数据
def insert_pub_page_name_data(db,cursor,recordid, publish_name,page_num,isdeal):# ISdeal = [str(isdeal)]*len(recordid)# data_tuple = tuple(zip(recordid, ISdeal))try:# 插入数据sql = "INSERT INTO imgs_list_path_form (recordid,publish_date,page_num,ISdeal) VALUES('%s','%s','%s','%s')"%(recordid, publish_name,page_num,isdeal)cursor.execute(sql)# cursor.executemany(sql, data_tuple)# 提交到数据库执行db.commit()print("successfully insert publish date data!")except Exception as e:print('insert multipy!', e)return Falsereturn True

４．查询

def find_pub_page_name_data(cursor,is_deal):# 要执行的sql语句sql = "select * from imgs_list_path_form where ISdeal ='%s'"%(is_deal)cursor.execute(sql)try:result = cursor.fetchall()except TypeError:print("An exception was raised")else:# print(result, "successfully find")print("successfully find publish date data!!!")# print('res:', result)return result

５．更新

def update_pub_page_name_data(db,cursor,recordid,publish_name,page_num):try:# 更改sql = "update imgs_list_path_form set ISdeal='1' where recordid='%s' AND publish_date='%s' AND page_num='%s'"%(recordid,publish_name,page_num)cursor.execute(sql)db.commit()print('update Success!')except Exception as e:print('update fail!',e)return Falsereturn True

６．删除

# 删除
def deleteRecord(db, cursor, key, value):# 要执行的sql语句sql = "delete from recordid_library where " + key + "=" + valuecursor.execute(sql)db.commit()print("successfully delete")

可视化数据库：

二．安装Navicat

首先上官网上下载LINUX版本： http://www.navicat.com.cn/download/navicat-premium
1．安装

1 下载 navicat110_mysql_en.tar.gz 文件

2.tar -zxvf xxx/navicat112_mysql_cs_x64

3 解压后进入解压后的目录运行命令：
./start_navicat

2．修改中文可视

连接上数据库后里面的中文数据是乱码,把Ubuntu的字符集修改为zh_CN.utf8就行了,修改方法:
1.查看系统支持的字符集: locale -a

2,修改字符集: export LANG=zh_CN.utf8

3.用vim命令打开start_navicat文件，会看到 export LANG=”en_US.UTF-8” 将这句话改为 export LANG=”zh_CN.UTF-8”。

3．破解
sudo rm -r /home/fzh/.navicat64/

删除后，再次启动navicat时，会加载wine的更新配置窗口，启动后之前用的连接名以及密码已经没有了，需要重新创建连接。

4．卸载

1.首先将Navicat 安装包删除，

2. rm -r ～/.navicat64

5.不断延长使用时间

cd ~/.navicat64/

rm -r *.reg

6.目前最新的

chmod +x navicat15-premium-cs.AppImage

./navicat15-premium-cs.AppImage

三.flask_sqlalchemy写数据库

官方文档：https://sqlalchemy-utils.readthedocs.io/en/latest/database_helpers.html

1.数据库不存在，进行创建

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy_utils.functions import database_exists, create_database
from flask_sqlalchemy import SQLAlchemy
from flask import Flask, jsonify, request
db = SQLAlchemy()#本地配置
username = 'root'
password = '123456'
ip = '127.0.0.1'
port = '3306'
database = "fzh_database"sql_url = "mysql+pymysql://{}:{}@{}:{}/{}?charset=utf8mb4".format(username, password, ip, port, database)
engine = create_engine(sql_url, encoding="utf8")# 数据库不存在的话就创建
if not database_exists(engine.url):create_database(engine.url)

2.创建表

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy_utils.functions import database_exists, create_database
from flask_sqlalchemy import SQLAlchemy
from flask import Flask, jsonify, request
db = SQLAlchemy()#本地配置
username = 'root'
password = '123456'
ip = '127.0.0.1'
port = '3306'
database = "fzh_database"sql_url = "mysql+pymysql://{}:{}@{}:{}/{}?charset=utf8mb4".format(username, password, ip, port, database)
app = Flask(__name__)app.config["SQLALCHEMY_DATABASE_URI"
] = sql_url# app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = Truedb.init_app(app)#创建表class AIRedFile(db.Model):__tablename__ = "ai_redfile"pid = db.Column("pid", db.String(255))file_id = db.Column("file_id", db.String(255))file_path = db.Column("file_path", db.String(255))is_deal = db.Column("is_deal", db.String(1))type_ = db.Column("type", db.String(5))img_id = db.Column("img_id", db.String(255))angle = db.Column("angle", db.String(5))page_num = db.Column("page_num", db.Integer)url = db.Column("url", db.String(255))gpu_id = db.Column("gpu_id", db.String(1))key_ID = db.Column("key_ID", db.Integer, primary_key=True, autoincrement=True)create_time = db.Column('create_time', db.DateTime)update_time = db.Column('update_time', db.DateTime)def __init__(self, pid, file_id, file_path, is_deal, type_, img_id, angle, page_num, url, gpu_id, create_time, update_time):self.pid = pidself.file_id = file_idself.file_path = file_pathself.is_deal = is_dealself.type_ = type_self.img_id = img_idself.angle = angleself.page_num = page_numself.url = urlself.gpu_id = gpu_idself.create_time = create_timeself.update_time = update_time
# Base.metadata.create_all(engine) #创建表结构
with app.app_context():db.create_all()

３．表的设计与增删改查调试

#coding:utf-8
"""
数据库的设计
"""
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime
db = SQLAlchemy()
class AIDaxin(db.Model):bank_id = db.Column("bank_id", db.String(255))bank_name = db.Column("bank_name", db.String(255))pid = db.Column("pid", db.String(255))file_pid = db.Column("file_pid", db.String(255))　＃自己设置自增idkey_ID = db.Column("key_ID", db.Integer, primary_key=True, autoincrement=True)file_path = db.Column("file_path", db.String(255))is_deal = db.Column("is_deal", db.String(1))create_time = db.Column('create_time', db.DateTime)update_time = db.Column('update_time', db.DateTime)__tablename__ = "ai_daxin"def __init__(self, bank_id, bank_name, pid, file_pid, file_path, is_deal, create_time, update_time):self.bank_id = bank_idself.bank_name = bank_nameself.pid = pidself.file_pid = file_pidself.file_path = file_pathself.is_deal = is_dealself.create_time = create_timeself.update_time = update_time#debug 使用
def ai_daxin_test():from flask import Flask, jsonify, requestapp = Flask(__name__)app.config["SQLALCHEMY_DATABASE_URI"] = "mysql+pymysql://root:123456@localhost:3306/fzh_local_test"# # # #增# import datetime# with app.app_context():#     test_news = AIDaxin('bank_id1', 'bank_name1','pid1', 'file_pid3', 'file_path3', '0', datetime.datetime.now(), None)#     db.session.add(test_news)#     db.session.commit()# 查# with app.app_context():#     pdf_infos = AIDaxin.query.filter_by(is_deal="0").all()# print('pdf_infos:', pdf_infos)# for pdf_info in pdf_infos:#     print('pdf_info.pid:', pdf_info.pid)#     print('pdf_info.file_pid:', pdf_info.file_pid)#     print('pdf_info.file_path:', pdf_info.file_path)#     print('pdf_info.is_deal:', pdf_info.is_deal)# #删# with app.app_context():#     newspapers = AINewspaper.query.filter_by(is_deal="0").first()#     db.session.delete(newspapers)#     db.session.commit()# print('newspapers:', newspapers)# 改# with app.app_context():#     pdf_infos = AIDaxin.query.filter_by(file_path="file_path2").first()#     pdf_infos.is_deal = '1'#     db.session.commit()if __name__ == '__main__':ai_dain_test()