Flask connects to existing tables in MySQL database

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Preface

flask Is based on python Of , More popular web frame , Want to do web Development inevitably needs to interact with the database , Now learn flask How to connect to the database .

One 、 Download related packages

download flask:

pip install flask

flask Specialized sql Processing packages , Use the following command to download ：

pip install flask-sqlalchemy

Two 、 Connect to database

Import related packages and create flask example

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
# establish Flask example 
app = Flask(__name__)

Then connect to the database and create database objects ：

#  Write about yourself mysql Username 、 password 、 Host name 、 Port and database name 
app.config['SQLALCHEMY_DATABASE_URI'] = "mysql://username:[email protected]:port/db"
#  Dynamically track database changes .  Poor performance .  And will be removed in future versions .  At present, it is only written to solve the prompt of the console 
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False
# Create database objects 
db = SQLAlchemy(app)

Finally, get the data of a table in the database ：

from flask import jsonify
@app.route('/')
def db_test():
    dict_show = {
    }  #  Define dictionary for data presentation 
    #  Reflect existing tables in the database , And get all existing table objects .
    db.reflect()
    #  Get all table names 
    all_table = {
    table_obj.name: table_obj for table_obj in db.get_tables_for_bind()}
    #  obtain demo All data of table 
    all_data = db.session.query(all_table['demo'])
    for data in all_data:
        print(data)  # View the data 
        dict_show[data[0]] = [data[1], data[2]]
    #  Translate the dictionary into json data 
    return jsonify(dict_show)

Finally check the results ：

You can see demo All the data in the table , Be accomplished ！

The last attached demo Complete code for ：

from flask import Flask, jsonify
from flask_sqlalchemy import SQLAlchemy

# establish Flask example 
app = Flask(__name__)
#  Write about yourself mysql Username 、 password 、 Host name 、 Port and database name 
app.config['SQLALCHEMY_DATABASE_URI'] = "mysql://username:[email protected]:port/db"
#  Dynamically track database changes .  Poor performance .  And will be removed in future versions .  At present, it is only written to solve the prompt of the console 
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False
# Create database objects 
db = SQLAlchemy(app)

@app.route('/')
def db_test():
    dict_show = {
    }  #  Define dictionary for data presentation 
    #  Reflect existing tables in the database , And get all existing table objects .
    db.reflect()
    #  Get all table names 
    all_table = {
    table_obj.name: table_obj for table_obj in db.get_tables_for_bind()}
    #  obtain demo All data of table 
    all_data = db.session.query(all_table['demo'])
    for data in all_data:
        print(data)  # View the data 
        dict_show[data[0]] = [data[1], data[2]]
    return jsonify(dict_show)

if __name__ == '__main__':
    app.run(debug=True)