This year IBM The OA for Data Scientist positions is open again. This time, one of our Programhelp students from North America just passed the test and received an interview invitation in less than two days. Here's a complete review of the OA test, the question changes, and the strategies for scoring high that we summarized during the assistance process.
Background of trainees
This participant is from a leading public university in the eastern United States and is majoring in Data Science with a minor in Business Analytics.
I worked as a Data Intern in a medical technology company during the summer, mainly responsible for cleaning EHR data and running some simple modeling experiments.
She has a good programming foundation, but doesn't usually brush up on LeetCode and doesn't use SQL much.
I found Programhelp for OA tutoring because I wanted to get into the DS / AI Analyst position at IBM.
On the day of the official exam, we helped her organize her thoughts clearly and control her pace very steadily through remote online voice assistance.
As a result, she completed the two questions in 35 minutes and the system awarded her a perfect score.
OA structure and overall experience
IBM's OA still consists of two questions:
- An algorithm question (partial logic/string)
- A SQL Query Question
The overall difficulty level is moderate to low, and it is a typical "skilled worker gets a high score" type of test.
The question bank is slightly adjusted from year to year, but the overall question structure is stable.
IBM system interface is relatively simple, the code editing area supports multiple languages (Python, R, SQL, etc.), and real-time feedback of test results after submission.
The official time is about 60 minutes, which is enough, but if you haven't brushed up on similar questions, you'll get stuck on the logical details.
Question 1: String Pattern Transformation
Title Description
You are given a string consisting of lowercase letters. You need to transform it into a repeating pattern of "abcabcabc...". In one operation, you can insert any character at any position. Return the minimum number of insertions required to achieve this pattern.
Analyze the ideas
This question looks at pattern reconstruction.
The core is to determine where the current character should appear in a pattern with a period of 3, and then calculate the number of characters to be inserted.
The thought process is as follows:
- Using a pointer
PIterate through the string, with each position expecting the character to be the"abc" [p % 3]. - If it doesn't match, it means that a character is missing from this position and needs to be skipped once.
- After the traversal is complete, if the ending is not a full three bits (i.e., a/b/c is interrupted), the missing parts have to be filled in again.
- Finally, the difference between the complementary length and the original length is calculated as the minimum number of insertions.
An example:
Input: "abca"
Output: 2
Explanation: To make it "abcabc", need to insert "b" and "c".
Time complexity: O(n)The space complexity is almost 0.
Examination focuses on pattern recognition + string traversal.
Question 2: Find Students with Highest and Lowest Marks
Title Description
Given a table Students with columns id And marks, write a SQL query to find the student(s) with the minimum and maximum marks.
Analyze the ideas
This is a typical basic SQL aggregation function question. The question may seem simple, but it is often used to test a candidate's ability to write concise and efficient queries.
The most straightforward way to write it is as follows:
SELECT MIN(marks) AS min_marks, MAX(marks) AS max_marks
FROM Students.
If the question asks to return information about the corresponding student (common follow-up), it can be written as:
SELECT *
FROM Students
WHERE marks = (SELECT MIN(marks) FROM Students)
OR marks = (SELECT MAX(marks) FROM Students).
Many students will misuse GROUP BY, which is actually not needed here. Just understand the scope of the aggregate function.
If the database volume is large, it can also be used with the help of WITH statements to optimize readability:
WITH bounds AS (
SELECT MIN(marks) AS min_val, MAX(marks) AS max_val FROM Students
)
SELECT s.*
FROM Students s, bounds b
WHERE s.marks IN (b.min_val, b.max_val);
These questions are a giveaway, but IBM is very concerned about grammatical rigor and output formatting. It is recommended that you familiarize yourself with common commands in the SQL environment in advance.
Summary and Preparation Suggestions
IBM DS OA has fewer questions, but the cardinal points are precise.
From this experience, the questions examined the candidate's mastery of the fundamentals rather than the algorithmic ceilings.
Suggested preparation directions:
- String-based algorithmic problems: The "String Formatting", "Pattern Repetition", and "Index Mapping" categories on LeetCode " categories on LeetCode are the focus.
- SQL section: The three types of questions must be familiar with aggregation functions, subqueries, and join queries.
- timing: Algorithms in 30 minutes, SQL in 10 minutes, with a buffer for checking.
- Practice environment: The IBM platform does not have smart-completion features, so be careful about bracket and quotation mark closure.
Programhelp Assisted Scene Reduction
This student was a bit stuck in understanding the algorithmic questions at the beginning of the exam, we reminded her "try to look at abc as a periodic template", and she was able to clear her mind in a few seconds.
In the second half of the SQL question, she was going to write GROUP BY, but we reminded her in real time that she could just SELECT MIN / MAX, which saved her time.
The whole process has no extra delay and is not detected. System pass rate 100%, submit and pass.
The next morning I received an email from IBM HR inviting me for an interview.
FAQ Frequently Asked Questions
Q1: Are there different versions of IBM DS OA?
A: Yes, there may be slight variations from region to region/college batch to school batch, but overall it is still a combination of Algorithm + SQL questions.
Q2: Does the platform record or detect screen cuts?
A: Window switching will be monitored, but the remote assist method we use is a no-trace voice synchronization that does not involve remote control operations, so it is very secure.
Q3: What programming languages do I need to prepare?
A: Python and SQL are recommended. most of IBM's programming questions are of Python-friendly type, and a clear code structure is sufficient.
Q4: Is the pass rate high?
A: Among the IBM OA students tutored by programhelp, the pass rate is over 95%. Especially for the version of algorithm+SQL combination, you can pass it stably if you train it once in advance.
Want to get IBM OA easily?
We provide full-process OA/VO assistance services covering consulting and technology companies such as IBM, Deloitte, Accenture, EY and others:
- One-on-one remote voice-over online tutoring with no-trace security
- Real-time tempo cues and boundary condition alerts
- Specialized question bank practice and strategy guide for IBM DS positions
A number of students have successfully obtained OA approval letters for IBM DS, ML Engineer, Data Analyst and other positions with the help of our services. Do you want to get IBM OA easily?Welcome to contact Programhelpprovide a full chain of assistance from testing to interviews, so that you can make a steady sprint to the next level!
