Count reoccurring variable within AWS-S3 bucket using S3-Select query - sql

Question

I'm running a Python script to query an AWS-S3 bucket using the AWS-S3-Select tool. I'm importing a variable from a txt file and want to pass it into the S3-Select query. I also want to count all imported variable recurrences (within a specified column) by querying the entire S3 directory instead of just a single file.
This is what I have so far:
import boto3
from boto3.session import Session
with open('txtfile.txt', 'r') as myfile:
variable = myfile.read()
ACCESS_KEY='accessKey'
SECRET_KEY='secredtKey'
session = Session(aws_access_key_id=ACCESS_KEY, aws_secret_access_key=SECRET_KEY)
s3b = session.client('s3')
r = s3b.select_object_content(
Bucket='s3BucketName',
Key='directory/fileName',
ExpressionType='SQL',
Expression="'select count(*)from S3Object s where s.columnName = %s;', [variable]",
InputSerialization={'CSV': {"FileHeaderInfo": "Use"}},
OutputSerialization={'CSV': {}},
)
for event in r['Payload']:
if 'Records' in event:
records = event['Records']['Payload'].decode('utf-8')
print(records)
elif 'Stats' in event:
statsDetails = event['Stats']['Details']
print("Stats details bytesScanned: ")
When I run this script I get back the following error:
Traceback (most recent call last):
File "s3_query.py", line 20, in <module>
OutputSerialization={'CSV': {}},
File "/root/anaconda3/lib/python3.6/site-packages/botocore/client.py", line 314, in _api_call
return self._make_api_call(operation_name, kwargs)
File "/root/anaconda3/lib/python3.6/site-packages/botocore/client.py", line 612, in _make_api_call
raise error_class(parsed_response, operation_name)
botocore.exceptions.ClientError: An error occurred (ParseUnexpectedToken) when calling the SelectObjectContent operation: Unexpected token found COMMA:',' at line 1, column 67.

Answer 1

This line looks quite strange:
Expression="'select count(*)from S3Object s where s.columnName = %s;', [variable]"
That is not normal SQL or Python syntax.
You should probably use:
Expression='select count(*)from S3Object s where s.columnName = %s;' % [variable]