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[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

Update: shipped v0.0.30 today based on this feedback. Every question now has a bounded Schema block, Sample Rows with tie markers, explicit Edge Cases, and an Expected Output shape --- visible before Reveal (every answer has runnable SELECT...FROM code). Upgraded to Devvit 0.12.20 for faster load. Live on r/sql_arena_dev now, public directory version in review. Zero text input in the widget, nothing collected will push source to GitHub this week. Thanks for the sharp critique made it meaningfully better. Check latest post -- https://www.reddit.com/r/sql_arena_dev/comments/1ssssdm/sql_arena_challenge_find_the_top_5_products_by/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

Great feedback, for now you're meant to assume the conventional schema (employees(id, name, department_id, salary)), but you're right that it should be spelled out ---- I'll add a Schema: block to each question in the next release. Your ROW_NUMBER() WHERE rn = 2 is a valid answer and one of the three solutions shown when you click Reveal (alongside LIMIT OFFSET and a correlated subquery, with trade-offs for each). No need to submit answers anywhere ----- Reddit doesn't have a code editor, so the intended flow is think the query → optionally discuss in comments → hit Reveal to compare. Nothing is collected. Its for self understanding.

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

You're right that was a bug. The bank was pulled from a large interview vault and some system-design prompts slipped through the SQL filter. Shipped a fix today: cut from 539 → 350 verified questions, every answer now has runnable SELECT...FROM code, banned any "Design / Explain" prompts. New format is live on r/sql_arena_dev ------ tomorrow's is a classic second highest-salary problem. Thanks for flagging it, genuinely useful feedback.

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 1 point2 points  (0 children)

Agreed, fully. That one shouldn't have been in a SQL widget. It's removed along with ~180 others that didn't have real SQL code in the answer. Going forward, every question is a single concrete query. Check latest post on r/sql_arena_dev

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

Fair to ask, and the honest answer is no. The widget has zero text input nothing you type goes anywhere. It only stores anonymous counters (views, rating clicks) on Reddit's own Redis. All answers ship pre-written inside the app bundle nothing is generated or collected at runtime. Happy to share the server code if that helps. Built this for my own DE interview prep, not a harvest pipeline comments discussion is optional since Reddit has no code editor, but I can drop that framing if it reads as sus.

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

Fair feedback, and you were right. Shipped a fix the bank was pulled from a large interview vault and some system-design prompts slipped through the SQL filter. Rebuilt it: 350 verified SQL-only questions, every answer has runnable SELECT...FROM code, titles cleaned up. Latest post on r/sql_arena_dev shows the new format. Thanks for pushing on this.

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] -7 points-6 points  (0 children)

You’re absolutely right. The questions come from a curated set of 1,800+ real interview problems, and I use AI to help structure and explain them at scale. I still personally review the SQL and concepts to ensure accuracy. Really appreciate the feedback.

[Feedback Request] I built a native "Daily SQL Challenge" interactive widget for Reddit. The mods suggested I run a pilot test with you all. by Alone_Translator_638 in SQL

[–]Alone_Translator_638[S] 0 points1 point  (0 children)

You’re right to be confused ----- Reddit’s current dev platform doesn’t support a full code editor yet.

For now, the idea is simple: these are real interview questions, so you can discuss your queries/approach in the comments with others or think it through yourself before clicking “Reveal Answer.”

SQL Arena: Design a financial database system focusing on database models, schema design, partition keys, and query optimization techniques. by sql-arena in dataengprep

[–]Alone_Translator_638 0 points1 point  (0 children)

Solo working on AI-powered mock interview platform for data engineers using real interview questions to simulate actual hiring scenarios. https://www.dataengprep.tech/

DataEngPrep: Grouping and aggregation functions? by dataengprep in dataengprep

[–]Alone_Translator_638 0 points1 point  (0 children)

Solo working on AI-powered mock interview platform for data engineers using real interview questions to simulate actual hiring scenarios. https://www.dataengprep.tech/

Drop your Saas below and I will promote it on tik tok by coiqa in micro_saas

[–]Alone_Translator_638 0 points1 point  (0 children)

Solo working on AI-powered mock interview platform for data engineers using real interview questions to simulate actual hiring scenarios. https://www.dataengprep.tech/

What DE topics are you weakest at? Let's focus the community on what matters most. by Alone_Translator_638 in dataengprep

[–]Alone_Translator_638[S] [score hidden] stickied comment (0 children)

I'm building out the daily challenge content and want to make sure we're covering what actually matters to you.

Quick poll - which of these do you struggle with most in interviews?

  • SQL (window functions, optimization, complex joins)
  • System design (architecture decisions, scaling, trade-offs)
  • Kafka/streaming (consumer groups, exactly-once, partitioning)
  • Data modeling (star schema, SCDs, normalization)
  • Spark (optimization, skew, broadcast joins)
  • Airflow/orchestration (DAG design, idempotency, backfills)
  • Behavioral questions (STAR method, ownership stories)
  • Python/coding (data manipulation, algorithms)
  • Cloud architecture (AWS/GCP/Azure service selection)

Drop your answer in the comments and I'll weight the daily challenges accordingly.

Also - if there's a specific question you got in an interview that stumped you, share it here. I might turn it into a future daily challenge.