SadServers: Linux, DevOps & SRE Labs | Job Interview Prep

Troubleshooting Scenarios: Data Processing

Linux & Bash

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Data Processing

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Languages

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csv data processing json sql

realistic / interviews new pro

Easy

#	Name	Time	Type
1	"Minneapolis": Break a CSV file	10 m	Do	"Minneapolis": Break a CSV file Scenario: "Minneapolis": Break a CSV file Level: Easy Type: Do Access: Email Description: Break the Comma Separated Valued (CSV) file data.csv in the /home/admin/ directory into exactly 10 smaller files of about the same size named data-00.csv, data-01.csv, ... , data-09.csv files in the same directory. All the files should have the same header (first line with column names) as data.csv. None of the smaller files should be bigger than 32KB. Note: to simplify, disregard broken lines in your files (ie, you can break a file at any point, not just at a newline). The resulting files don't have to be proper CSV files. Test: The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 10 minutes.
2	"Saint Paul": Merge Many CSVs files	15 m	Do	"Saint Paul": Merge Many CSVs files Scenario: "Saint Paul": Merge Many CSVs files Level: Easy Type: Do Access: Email Description: Join (merge) all the 338 files in /home/admin/polldayregistrations_enregistjourduscrutin?????.csv into one single /home/admin/all.csv file with the contents of all the CSV files in any order. There should be only one line with the names of the columns as a header. Test: The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 15 minutes.
3	"Hamburg": Find the AWS EC2 volume	30 m	Do Pro	"Hamburg": Find the AWS EC2 volume Scenario: "Hamburg": Find the AWS EC2 volume Level: Easy Type: Do Access: Paid Description: We have a lot of AWS EBS volumes, the description of which we have save to a file with: `aws ec2 describe-volumes > aws-volumes.json`. One of the volumes contains important data and we need to identify which volume (its ID), but we only remember these characteristics: gp3, created before 30/09/2025 , Size < 64 , Iops < 1500, Throughput > 300. Find the correct volume and put its "InstanceId" into the ~/mysolution file, e.g.: `echo "vol-00000000000000000" > ~/mysolution` Test: Running `md5sum /home/admin/mysolution` returns `e7e34463823bf7e39358bf6bb24336d8` (we also accept the file without a new line at the end). The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 30 minutes.

Medium

#	Name	Time	Type
1	"Unimak Island": Fun with Mr Jason	15 m	Do Pro	"Unimak Island": Fun with Mr Jason Scenario: "Unimak Island": Fun with Mr Jason Level: Medium Type: Do Access: Paid Description: Using the file station_information.json , find the station_id where "has_kiosk" is false and "capacity" is greater than 30. Save the station_id of the solution in the /home/admin/mysolution file, for example: `echo "ec040a94-4de7-4fb3-aea0-ec5892034a69" > ~/mysolution` You can use the installed utilities jq, gron, jid as well as Python3 and Golang. Test: `md5sum /home/admin/mysolution` returns `8d8414808b15d55dad857fd5aeb2aebc` Time to Solve: 15 minutes.
2	"Ivujivik": Parlez-vous Français?	20 m	Do Pro	"Ivujivik": Parlez-vous Français? Scenario: "Ivujivik": Parlez-vous Français? Level: Medium Type: Do Access: Paid Description: Given the CSV file /home/admin/table_tableau11.csv, find the Electoral District Name/Nom de circonscription that has the largest number of Rejected Ballots/Bulletins rejetés and also has a population of less than 100,000. The initial CSV file may be corrupted or invalid in a way that can be fixed without changing its data. Installed in the VM are: Python3, Go, sqlite3, miller directly and PostgreSQL, MySQL in Docker images. Save the solution in the /home/admin/mysolution , with the name as it is in the file, for example: `echo "Trois-Rivières" > ~/mysolution` (the solution must be terminated by newline). Test: `md5sum` /home/admin/mysolution returns `e399d171f21839a65f8f8ab55ed1e1a1` Time to Solve: 20 minutes.
3	"Atrani": Modify a SQlite3 Database	15 m	Fix Pro	"Atrani": Modify a SQlite3 Database Scenario: "Atrani": Modify a SQlite3 Database Level: Medium Type: Fix Access: Paid Description: A developer created a script /home/admin/readdb.py that tests access to a database. Without modifying the readdb.py file, change the database so that running the script returns the string "John Karmack". Test: Running /home/admin/readdb.py returns "John Karmack". The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 15 minutes.
4	"Minneapolis with a Vengeance": Break a CSV file	20 m	Do	"Minneapolis with a Vengeance": Break a CSV file Scenario: "Minneapolis with a Vengeance": Break a CSV file Level: Medium Type: Do Access: Email Description: Break the Comma Separated Valued (CSV) file data.csv in the /home/admin/ directory into exactly 10 smaller files of about the same size named data-00.csv, data-01.csv, ... , data-09.csv files in the same directory. All the files should have the same header (first line with column names) as data.csv. None of the smaller files should be bigger than 32KB. Note: unlike the original Minneapolis scenario, here the resulting files have to be proper CSV files. As a helper tool, you can run the program check_csv.py to check if your data-??.cs files look like proper CSV files. Test: The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 20 minutes.