I have a Python application using aiomysql to interact with a MySQL database. I’m running a query that executes quickly in HeidiSQL but takes significantly longer when executed through my application.

Here is the relevant code:

router_mysql.py:

COMMON_QUERY_PART = """
    SELECT
        sm.*,
        lm.className
    FROM
        data_{suffix} sm
    JOIN
        names_{suffix} lm ON sm.materialType = lm.id
"""

@router.get("/all/")
async def get_all_statistics(suffix: str):
    connection = await connect_to_mysql()
    async with connection.cursor() as cursor:
        query = COMMON_QUERY_PART.format(suffix=suffix)
        try:
            await cursor.execute(query)
            statistics = await cursor.fetchall()
        except Exception as e:
            connection.close()
            raise HTTPException(status_code=400, detail=str(e))
    connection.close()
    return {"statistics": statistics}

mysql.py:

import aiomysql
import os
from dotenv import load_dotenv

load_dotenv()

async def connect_to_mysql():
    connection = await aiomysql.connect(
        host=os.getenv("DB_HOST"),
        port=int(os.getenv("DB_PORT")),
        user=os.getenv("DB_USER"),
        password=os.getenv("DB_PASSWORD"),
        db=os.getenv("DB_DATABASE"),
        charset="utf8mb4",
        cursorclass=aiomysql.cursors.DictCursor
    )
    return connection

When I run the query in HeidiSQL, it executes very quickly. However, when I execute the same query in my Python application using aiomysql, it takes a significantly longer time.

My questions are:

What could be causing the discrepancy in execution time between HeidiSQL and aiomysql?

Are there any specific configurations or best practices for using aiomysql that might improve performance?

Could the async nature of aiomysql be contributing to the slowdown, and if so, how can I mitigate this?

Any insights or suggestions would be greatly appreciated!