Allowed R6 · Within policy
{
"slug": "problem-solving-database-round",
"title": "Problem Solving and Database Round",
"difficulty": "medium",
"tags": [
"coding",
"sql",
"technical",
"swe",
"backend"
],
"is_free": true,
"locked": false,
"frequency": 0.333,
"last_reported_at": "2025-05-05T17:12:36.819910Z",
"url": "https://www.mokabla.com/en/c/breadfast/problem-solving-database-round",
"agent": {
"page": "https://www.mokabla.com/agent/en/c/breadfast/problem-solving-database-round",
"question": "https://www.mokabla.com/agent/_call/get_question?company=breadfast&question=problem-solving-database-round"
},
"company": {
"slug": "breadfast",
"name_en": "Breadfast"
},
"body_md": "## What they ask\n\nAn online technical interview that mixes a problem-solving exercise with database questions, followed later by an engineering manager conversation.\n\n**Problem-solving sample** (solve in the starter code): delivery slots are given as `[start, end]` minute intervals for one rider; merge overlapping or touching slots so the rider has the fewest continuous windows.\n\n**Database questions** in this area, for example:\n\n- Write a query for the top 5 products by revenue per day over the last week.\n- What index would you add for \"orders by customer, newest first\", and why a composite index order matters.\n- Normalization: when you would denormalize an orders table for reporting.\n- Transactions: what isolation level prevents two checkouts from overselling the last unit.\n\n## Examples\n\n- `[[0,30],[5,10],[35,50],[50,60]]` returns `[[0,30],[35,60]]`.\n- `[[10,20]]` returns `[[10,20]]`.\n\n## Constraints\n\n- Up to `10^4` intervals; O(n log n) via sorting is expected.\n\n## What they look for\n\n- Sorting by start and a single sweep, with the touching-interval case handled (`50` meets `50`).\n- Practical SQL: joins, aggregates, and indexing reasoning.\n- Clear communication; the interviewer shares screen and asks you to narrate.",
"follow_ups_md": "- Return the largest free gap between slots as well.\n- How does your SQL change if revenue must exclude cancelled orders?",
"access": "Question bodies are paid content: a person buys 30 days of access per company (200 EGP or 200 points) in the human app. Agents get titles, tags and difficulty; bodies only for free questions."
}