React Interview Question: useMemo vs useCallback vs React.memo
Short answer: useMemo caches a computed value , useCallback caches a function , and React.memo skips re-rendering a component when its props...
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SQL Interview Question: Explain Normalisation (1NF, 2NF, 3NF)
Short answer: normalisation organises tables to reduce duplicated data and prevent update anomalies. Each normal form removes a specific kin...
System Design Interview Question: How Does Load Balancing Work?
Short answer: a load balancer spreads incoming requests across multiple servers so no single server is overloaded, and routes around servers...
Counting Tokens and Estimating LLM API Costs
LLM APIs bill by the token , a chunk of text that is often a word or part of a word. Input and output tokens are priced separately, and outp...
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