S3选择CSV标头 [英] S3 Select CSV Headers

问题描述

我正在使用S3选择从S3存储桶读取csv文件并以CSV输出.在输出中，我仅看到行，而没有标题.如何获得包含标头的输出.

I am using S3 Select to read csv file from S3 Bucket and outputting as CSV. In the output I only see rows, but not headers. How do I get output with headers included.

import boto3

s3 = boto3.client('s3')

r = s3.select_object_content(
        Bucket='demo_bucket',
        Key='demo.csv',
        ExpressionType='SQL',
        Expression="select * from s3object s",
        InputSerialization={'CSV': {"FileHeaderInfo": "Use"}},
        OutputSerialization={'CSV': {}},
)

for event in r['Payload']:
    if 'Records' in event:
        records = event['Records']['Payload'].decode('utf-8')
        print(records)

CSV

Name, Age, Status
Rob, 25, Single
Sam, 26, Married

s3select的输出

Output from s3select

Rob, 25, Single
Sam, 26, Married

推荐答案

更改InputSerialization={'CSV': {"FileHeaderInfo": "Use"}},

到 InputSerialization={'CSV': {"FileHeaderInfo": "NONE"}},

TO InputSerialization={'CSV': {"FileHeaderInfo": "NONE"}},

然后，它将打印完整的内容，包括标题.

Then, it will print full content, including the header.

说明:

FileHeaderInfo接受"NONE | USE | IGNORE"之一.

FileHeaderInfo accepts one of "NONE|USE|IGNORE".

使用NONE选项而不是USE，它还会打印标题，因为NONE告诉您还需要标题来进行处理.

Use NONE option rather then USE, it will then print header as well, as NONE tells that you need header as well for processing.

这里是参考. https://boto3. amazonaws.com/v1/documentation/api/latest/reference/services/s3.html#S3.Client.select_object_content

希望对您有帮助.

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