Pandasql table not found error on AWS Lambda Function which works on local machine - pandas

Question

I am reading a pandas DF from AWS S3, trying to run some pre-processing SQL on it and save as a csv again, using pandasql library for the same. Challenge here is, in my local machine it works perfectly fine, but on the AWS Lambda it fails with the following error:
"An error occured: (sqlite3.OperationalError) no such table: TblV\n[SQL: SELECT * from TblV;]\n(Background on this error at: http://sqlalche.me/e/e3q8)"
Note: I've built a deployment package of pandas and pandasql on Amazon AMI Linux EC2 instance, zipped it with the lambda_function code and pushed to AWS S3 and saved in the Lambda Function by passing the path.
My code in local, which work perfectly fine:
import pandas as pd
from pandasql import sqldf
from time import time
t1 = time()
TblV = pd.read_csv(r"C:\Users\ab\Documents\test.csv")
query = """SELECT * from TblV"""
df = sqldf(query, globals())
print(df.columns)
print(df.shape)
print(df.head(5))
t2 = time()
print('Time taken: ', t2 - t1)
My code in AWS Lambda Function which throws the above error no matter what I do:
import json
import boto3
import datetime
import pandas as pd
from pandasql import sqldf
import sys
from io import StringIO
def lambda_handler(event, context):
try:
client = boto3.client('s3')
bucket_name = 'bucket'
object_key = 'test/Vol/test.csv'
csv_obj = client.get_object(Bucket=bucket_name, Key=object_key)
body = csv_obj['Body']
csv_string = body.read().decode('utf-8')
TblV = pd.read_csv(StringIO(csv_string))
print(TblV.head(5)) # This print works perfectly
query = """SELECT * from TblV;"""
df = sqldf(query, globals())
print(df.columns)
print(df.shape)
print(df.head(5))
except Exception as e:
err = "An error occured: " + str(e)
return err

Answer 1

you need to download the find in the tmp folder. AWS lambda has temporary storage of 500MB.
client.download_file(bucket_name, object_key,'/tmp/file_name.extension')
in order to read the data
TblV = pd.read_csv(r"/tmp/file_name.extension")
query = """SELECT * from TblV"""

Answer 2

Try using 'df = sqldf(query, locals())' instead of 'df = sqldf(query, globals())'.
The variable 'TblV' is defined inside a function hence it cant be reffered as a global variable.