由于AWS Redshift Spectrum不支持某些Parquet文件,所以需进行转换。以下是一个示例代码,可将Parquet文件转换为AWS Redshift Spectrum支持的格式:
首先,安装以下库pandas, pyarrow和boto3:
pip install pandas pip install pyarrow pip install boto3
在转换之前,请确保您已经将Parquet文件存储在Amazon S3上,并且可以访问该存储桶。
创建以下Python代码,将从Amazon S3上面拉取Parquet文件,进行转换后重新保存为CSV格式:
import boto3 import pyarrow.parquet as pq import pandas as pd
def convert_parquet_to_csv(s3_bucket, parquet_file_path, output_file_path): """Converts Parquet file to CSV"""
# Connect to Amazon S3
s3 = boto3.resource('s3')
# Load the Parquet file from S3
bucket = s3.Bucket(s3_bucket)
obj = bucket.Object(parquet_file_path)
body = obj.get()['Body'].read()
table = pq.read_table(body)
# Convert the Parquet table to Pandas dataframe
df = table.to_pandas()
# Save the Pandas dataframe as CSV file
df.to_csv(output_file_path, index=False)
print("Parquet file converted to CSV successfully!")
convert_parquet_to_csv('my-s3-bucket', 'my-parquet-file.parquet', 'my-csv-file.csv')
此时,您已经将包含转换后的CSV文件下载到本地,只需要将CSV文件上传至Amazon S3即可使用AWS Redshift Spectrum查询。