如何使用python jaydebeapi从Apache Derby DB读取数据blob？

import jaydebeapi

# Apache Derby JDBC驱动的路径
driver_path = "/path/to/derby-jdbc-driver.jar"

# Apache Derby数据库连接URL
url = "jdbc:derby://localhost:1527/sample"

# 连接到Apache Derby数据库
conn = jaydebeapi.connect("org.apache.derby.jdbc.ClientDriver", url, [username, password], driver_path)

# 创建游标对象
cursor = conn.cursor()

# 执行SQL查询
cursor.execute("SELECT CAST(blob_column AS VARBINARY) FROM table_name")

# 获取查询结果
result = cursor.fetchall()

# 关闭游标
cursor.close()

import io
from PIL import Image

# 获取BLOB数据
blob_data = result[0][0]

# 将BLOB数据转换为字节流
byte_stream = io.BytesIO(blob_data)

# 使用PIL库打开字节流
image = Image.open(byte_stream)

# 进行进一步处理
# ...