t.py

import mysql.connector

# Establish a connection
connection = mysql.connector.connect(
    host='your_host',
    user='your_username',
    password='your_password',
    database='your_database'
)

# Create a buffered cursor
cursor = connection.cursor(buffered=True)

# Execute a query
cursor.execute("SELECT * FROM your_table")

# Fetch rows in batches
batch_size = 100  # Adjust the batch size as needed
rows = cursor.fetchmany(batch_size)
while rows:
    for row in rows:
        print(row)
    rows = cursor.fetchmany(batch_size)

# Close the cursor and connection
cursor.close()
connection.close()

https://stackoverflow.com/a/32627190/4417821