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Connect to TiDB with peewee
Learn how to connect to TiDB using peewee. This tutorial gives Python sample code snippets that work with TiDB using peewee.

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.

Note:

This tutorial works with TiDB Cloud Serverless, TiDB Cloud Dedicated, and TiDB Self-Managed clusters.

Prerequisites

To complete this tutorial, you need:

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

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

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.

  1. Navigate to the Clusters page, and then click the name of your target cluster to go to its overview page.

  2. Click Connect in the upper-right corner. A connection dialog is displayed.

  3. Ensure the configurations in the connection dialog match your operating environment.

    • Connection Type is set to Public
    • Branch is set to main
    • Connect With is set to General
    • Operating System matches your environment.

    Tip:

    If your program is running in Windows Subsystem for Linux (WSL), switch to the corresponding Linux distribution.

  4. Click Generate Password to create a random password.

    Tip:

    If you have created a password before, you can either use the original password or click Reset Password to generate a new one.

  5. Run the following command to copy .env.example and rename it to .env:

    cp .env.example .env
  6. Copy and paste the corresponding connection string into the .env file. The example result is as follows:

    TIDB_HOST='{host}'  # e.g. gateway01.ap-northeast-1.prod.aws.tidbcloud.com
    TIDB_PORT='4000'
    TIDB_USER='{user}'  # e.g. xxxxxx.root
    TIDB_PASSWORD='{password}'
    TIDB_DB_NAME='test'
    CA_PATH='{ssl_ca}'  # e.g. /etc/ssl/certs/ca-certificates.crt (Debian / Ubuntu / Arch)

    Be sure to replace the placeholders {} with the connection parameters obtained from the connection dialog.

  7. Save the .env file.

  1. Navigate to the Clusters page, and then click the name of your target cluster to go to its overview page.

  2. Click Connect in the upper-right corner. A connection dialog is displayed.

  3. In the connection dialog, select Public from the Connection Type drop-down list, and then click CA cert to download the CA certificate.

    If you have not configured the IP access list, click Configure IP Access List or follow the steps in Configure an IP Access List to configure it before your first connection.

    In addition to the Public connection type, TiDB Dedicated supports Private Endpoint and VPC Peering connection types. For more information, see Connect to Your TiDB Dedicated Cluster.

  4. Run the following command to copy .env.example and rename it to .env:

    cp .env.example .env
  5. Copy and paste the corresponding connection string into the .env file. The example result is as follows:

    TIDB_HOST='{host}'  # e.g. tidb.xxxx.clusters.tidb-cloud.com
    TIDB_PORT='4000'
    TIDB_USER='{user}'  # e.g. root
    TIDB_PASSWORD='{password}'
    TIDB_DB_NAME='test'
    CA_PATH='{your-downloaded-ca-path}'

    Be sure to replace the placeholders {} with the connection parameters obtained from the connection dialog, and configure CA_PATH with the certificate path downloaded in the previous step.

  6. Save the .env file.

  1. Run the following command to copy .env.example and rename it to .env:

    cp .env.example .env
  2. Copy and paste the corresponding connection string into the .env file. The example result is as follows:

    TIDB_HOST='{tidb_server_host}'
    TIDB_PORT='4000'
    TIDB_USER='root'
    TIDB_PASSWORD='{password}'
    TIDB_DB_NAME='test'

    Be sure to replace the placeholders {} with the connection parameters, and remove the CA_PATH line. If you are running TiDB locally, the default host address is 127.0.0.1, and the password is empty.

  3. Save the .env file.

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

Need help?

Ask the community on Discord or Slack, or submit a support ticket.

Ask the community on Discord or Slack, or submit a support ticket.