Databases · INTERVIEW GUIDE
Practice this topicMongoDB & Mongoose
Document modeling, aggregation, indexes, and consistency.
20 questions
How do I fix slow aggregation, pagination or N+1 queries?
Query performance depends on how much data is scanned, joined, sorted and returned for each useful result. Slow pagination and N+1 patterns often do repeated work that grows with result size. The best fix usually reduces that work before increasing hardware or connection limits.
Advanced2 min read
What is a simple aggregation example?
This pipeline is a reporting query that first selects paid orders and then totals each customer's amount. Grouping reduces many order documents into one result per customer, after which sorting and limiting choose the top five. It demonstrates why filtering before expensive aggregation can be valuable.
Advanced2 min read
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