Connect to TiDB with peewee

TiDB is a MySQL-compatible database, and peewee is a popular Object Relational Mapper (ORM) for Python.

In this tutorial, you can learn how to use TiDB and peewee to accomplish the following tasks:

• Set up your environment.
• Connect to your TiDB cluster using peewee.
• Build and run your application. Optionally, you can find sample code snippets for basic CRUD operations.

Prerequisites

To complete this tutorial, you need:

• Python 3.8 or higher.
• Git.
• A TiDB cluster.

If you don't have a TiDB cluster, you can create one as follows:

• (Recommended) Follow Creating a TiDB Serverless cluster to create your own TiDB Cloud cluster.
• Follow Deploy a local test TiDB cluster or Deploy a production TiDB cluster to create a local cluster.

Run the sample app to connect to TiDB

This section demonstrates how to run the sample application code and connect to TiDB.

Step 1: Clone the sample app repository

Run the following commands in your terminal window to clone the sample code repository:

git clone https://github.com/tidb-samples/tidb-python-peewee-quickstart.git
cd tidb-python-peewee-quickstart

Step 2: Install dependencies

Run the following command to install the required packages (including peewee and PyMySQL) for the sample app:

pip install -r requirements.txt

Why use PyMySQL?

Peewee is an ORM library that works with multiple databases. It provides a high-level abstraction of the database, which helps developers write SQL statements in a more object-oriented way. However, peewee does not include a database driver. To connect to a database, you need to install a database driver. This sample application uses PyMySQL as the database driver, which is a pure Python MySQL client library that is compatible with TiDB and can be installed on all platforms. For more information, refer to peewee official documentation.

Step 3: Configure connection information

Connect to your TiDB cluster depending on the TiDB deployment option you've selected.

• TiDB Serverless
• TiDB Dedicated
• TiDB Self-Hosted

Step 4: Run the code and check the result

1. Execute the following command to run the sample code:

   python peewee_example.py
   

2. Check the Expected-Output.txt to see if the output matches.

Sample code snippets

You can refer to the following sample code snippets to complete your own application development.

For complete sample code and how to run it, check out the tidb-samples/tidb-python-peewee-quickstart repository.

Connect to TiDB

from peewee import MySQLDatabase

def get_db_engine():
    config = Config()
    connect_params = {}
    if ${ca_path}:
        connect_params = {
            "ssl_verify_cert": True,
            "ssl_verify_identity": True,
            "ssl_ca": ${ca_path},
        }
    return MySQLDatabase(
        ${tidb_db_name},
        host=${tidb_host},
        port=${tidb_port},
        user=${tidb_user},
        password=${tidb_password},
        **connect_params,
    )

When using this function, you need to replace ${tidb_host}, ${tidb_port}, ${tidb_user}, ${tidb_password}, ${tidb_db_name} and ${ca_path} with the actual values of your TiDB cluster.

Define a table

from peewee import Model, CharField, IntegerField

db = get_db_engine()

class BaseModel(Model):
    class Meta:
        database = db

class Player(BaseModel):
    name = CharField(max_length=32, unique=True)
    coins = IntegerField(default=0)
    goods = IntegerField(default=0)

    class Meta:
        table_name = "players"

For more information, refer to peewee documentation: Models and Fields.

Insert data

# Insert a single record
Player.create(name="test", coins=100, goods=100)

# Insert multiple records
Player.insert_many(
    [
        {"name": "test1", "coins": 100, "goods": 100},
        {"name": "test2", "coins": 100, "goods": 100},
    ]
).execute()

For more information, refer to Insert data.

Query data

# Query all records
players = Player.select()

# Query a single record
player = Player.get(Player.name == "test")

# Query multiple records
players = Player.select().where(Player.coins == 100)

For more information, refer to Query data.

Update data

# Update a single record
player = Player.get(Player.name == "test")
player.coins = 200
player.save()

# Update multiple records
Player.update(coins=200).where(Player.coins == 100).execute()

For more information, refer to Update data.

Delete data

# Delete a single record
player = Player.get(Player.name == "test")
player.delete_instance()

# Delete multiple records
Player.delete().where(Player.coins == 100).execute()

For more information, refer to Delete data.

Next steps

• Learn more usage of peewee from the documentation of peewee.
• Learn the best practices for TiDB application development with the chapters in the Developer guide, such as Insert data, Update data, Delete data, Single table reading, Transactions, and SQL performance optimization.
• Learn through the professional TiDB developer courses and earn TiDB certifications after passing the exam.

Need help?

Ask questions on the Discord, or create a support ticket.