[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"me":3,"catalog:en:backend\u002Fcaching":4,"config":253},null,{"field_key":5,"field_name":6,"seniority":7,"topic_key":8,"topic_name":9,"spec_key":7,"spec_name":7,"locale":10,"cell_total":11,"field_total":12,"seniorities":13,"topics":17,"specs":148,"samples":168},"backend","Backend","","caching","Caching","en",75,3300,[14,15,16],"junior","mid","senior",[18,21,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64,67,70,73,76,79,82,85,88,91,94,97,100,103,106,109,112,115,118,121,124,127,130,133,136,139,142,145],{"key":19,"name":20,"count":11},"api-design","API Design",{"key":8,"name":9,"count":11},{"key":23,"name":24,"count":11},"concurrency","Concurrency",{"key":26,"name":27,"count":11},"csharp-concurrency-async","Csharp Concurrency Async",{"key":29,"name":30,"count":11},"csharp-exceptions","Csharp Exceptions",{"key":32,"name":33,"count":11},"csharp-generics-interfaces","Csharp Generics Interfaces",{"key":35,"name":36,"count":11},"csharp-memory-performance","Csharp Memory Performance",{"key":38,"name":39,"count":11},"csharp-stdlib-http","Csharp Stdlib Http",{"key":41,"name":42,"count":11},"csharp-testing-tooling","Csharp Testing Tooling",{"key":44,"name":45,"count":11},"databases-sql","Databases \u002F SQL",{"key":47,"name":48,"count":11},"go-concurrency","Go Concurrency",{"key":50,"name":51,"count":11},"go-errors","Go Errors",{"key":53,"name":54,"count":11},"go-interfaces-generics","Go Interfaces Generics",{"key":56,"name":57,"count":11},"go-memory-performance","Go Memory Performance",{"key":59,"name":60,"count":11},"go-stdlib-http","Go Stdlib Http",{"key":62,"name":63,"count":11},"go-testing-tooling","Go Testing Tooling",{"key":65,"name":66,"count":11},"java-concurrency","Java Concurrency",{"key":68,"name":69,"count":11},"java-exceptions","Java Exceptions",{"key":71,"name":72,"count":11},"java-generics-interfaces","Java Generics Interfaces",{"key":74,"name":75,"count":11},"java-memory-jvm","Java Memory Jvm",{"key":77,"name":78,"count":11},"java-stdlib-http","Java Stdlib Http",{"key":80,"name":81,"count":11},"java-testing-tooling","Java Testing Tooling",{"key":83,"name":84,"count":11},"messaging-queues","Messaging \u002F Queues",{"key":86,"name":87,"count":11},"networking-http","Networking \u002F HTTP",{"key":89,"name":90,"count":11},"nodejs-error-handling","Nodejs Error Handling",{"key":92,"name":93,"count":11},"nodejs-event-loop-async","Nodejs Event Loop Async",{"key":95,"name":96,"count":11},"nodejs-memory-performance","Nodejs Memory Performance",{"key":98,"name":99,"count":11},"nodejs-modules-streams","Nodejs Modules Streams",{"key":101,"name":102,"count":11},"nodejs-stdlib-http","Nodejs Stdlib Http",{"key":104,"name":105,"count":11},"nodejs-testing-tooling","Nodejs Testing Tooling",{"key":107,"name":108,"count":11},"php-concurrency-async","Php Concurrency Async",{"key":110,"name":111,"count":11},"php-exceptions","Php Exceptions",{"key":113,"name":114,"count":11},"php-generics-interfaces","Php Generics Interfaces",{"key":116,"name":117,"count":11},"php-memory-performance","Php Memory Performance",{"key":119,"name":120,"count":11},"php-stdlib-http","Php Stdlib Http",{"key":122,"name":123,"count":11},"php-testing-tooling","Php Testing Tooling",{"key":125,"name":126,"count":11},"python-concurrency-async","Python Concurrency Async",{"key":128,"name":129,"count":11},"python-errors-context","Python Errors Context",{"key":131,"name":132,"count":11},"python-memory-performance","Python Memory Performance",{"key":134,"name":135,"count":11},"python-stdlib-http","Python Stdlib Http",{"key":137,"name":138,"count":11},"python-testing-tooling","Python Testing Tooling",{"key":140,"name":141,"count":11},"python-typing-oop","Python Typing Oop",{"key":143,"name":144,"count":11},"security","Security",{"key":146,"name":147,"count":11},"testing","Testing",[149,153,156,159,162,165],{"key":150,"name":151,"count":152},"csharp","C#\u002F.NET",450,{"key":154,"name":155,"count":152},"go","Go",{"key":157,"name":158,"count":152},"java","Java",{"key":160,"name":161,"count":152},"nodejs","Node.js",{"key":163,"name":164,"count":152},"php","PHP",{"key":166,"name":167,"count":152},"python","Python",[169,187,200,213,227,240],{"id":170,"topic":9,"difficulty":171,"body":172,"options":173,"correct_key":178,"explanation":186},"019f56bb-b33c-7a92-9888-fbbfb5818421",1,"What is the primary purpose of adding a cache in front of a slow data source?",[174,177,180,183],{"key":175,"text":176},"a","To encrypt frequently accessed data so it is served more securely",{"key":178,"text":179},"b","To keep frequently accessed data in fast storage, reducing latency and load on the source",{"key":181,"text":182},"c","To guarantee that cached data is stored durably and survives process restarts and machine crashes",{"key":184,"text":185},"d","To reduce the overall memory consumption of the application at runtime","A cache trades memory for speed: frequently requested data is served from fast storage instead of being recomputed or re-read, which cuts both response time and load on the backing source. Durability (c) is the opposite of what caches offer — cached data is typically volatile — and caches consume extra memory rather than saving it (d).",{"id":188,"topic":9,"difficulty":171,"body":189,"options":190,"correct_key":175,"explanation":199},"019f56bb-b33d-7535-a229-5c93d3e06f72","In caching terminology, what is a **cache hit**?",[191,193,195,197],{"key":175,"text":192},"The requested data is found in the cache and served from it",{"key":178,"text":194},"The requested data is not in the cache, so the source must be queried",{"key":181,"text":196},"The cache is full and an existing entry must be evicted",{"key":184,"text":198},"A cached entry has become inconsistent with the source data","A hit means the lookup succeeded and the request is served from the cache. Option (b) describes a cache miss, (c) describes eviction, and (d) describes staleness — three related but distinct concepts.",{"id":201,"topic":9,"difficulty":171,"body":202,"options":203,"correct_key":181,"explanation":212},"019f56bb-b33e-7387-a06c-a9f0b7b8b2a0","A cache reports a 95% hit ratio. What does this metric mean?",[204,206,208,210],{"key":175,"text":205},"The cache is using 95% of its allocated memory",{"key":178,"text":207},"95% of the cached entries are still consistent with the source",{"key":181,"text":209},"95% of lookups were answered from the cache",{"key":184,"text":211},"95% of write operations were routed through the cache","Hit ratio is hits divided by total lookups: at 95%, only 5% of reads had to reach the backing store. The metric says nothing about memory usage (a) or about how fresh the entries are (b).",{"id":214,"topic":9,"difficulty":215,"body":216,"options":217,"correct_key":175,"explanation":226},"019f56bb-b33e-7be8-8890-cd9f3dd161d8",2,"What is the fundamental trade-off when choosing a TTL (time-to-live) for cached entries?",[218,220,222,224],{"key":175,"text":219},"A longer TTL raises the hit ratio but widens the stale-data window",{"key":178,"text":221},"A longer TTL makes data fresher but increases memory usage",{"key":181,"text":223},"A shorter TTL improves both freshness and hit ratio at the same time",{"key":184,"text":225},"TTL affects only write throughput, not read behavior","Entries that live longer are found in the cache more often (higher hit ratio) but can lag further behind the source (staleness). A shorter TTL buys freshness at the cost of more misses — you cannot maximize both, which is why (c) is wrong.",{"id":228,"topic":9,"difficulty":215,"body":229,"options":230,"correct_key":181,"explanation":239},"019f56bb-b33f-7a29-b554-5a50a2dab0a7","```\nvalue = cache.get(key)\nif value == null:\n    value = db.query(key)\n    cache.set(key, value, ttl=300)\nreturn value\n```\nWhich caching pattern does this code implement?",[231,233,235,237],{"key":175,"text":232},"Write-through: writes update the cache and the database together",{"key":178,"text":234},"Read-through: the cache library itself loads missing values from the database",{"key":181,"text":236},"Cache-aside: the application checks the cache and loads\u002Fpopulates it on a miss",{"key":184,"text":238},"Write-behind: writes are buffered in the cache and flushed to the database later","The application code itself handles the miss: it queries the database and fills the cache. That is cache-aside (lazy loading). In read-through (b) the cache component — not the application — performs the load; (a) and (d) describe write paths, while this snippet is a read path.",{"id":241,"topic":9,"difficulty":215,"body":242,"options":243,"correct_key":184,"explanation":252},"019f56bb-b340-720f-95f8-34c4ea731c54","In a write-through caching strategy, what happens when the application writes data?",[244,246,248,250],{"key":175,"text":245},"The write goes only to the cache; the database is updated asynchronously later",{"key":178,"text":247},"The write goes only to the database; the cache picks up the new value on the next read",{"key":181,"text":249},"The write clears the entire cache to avoid any inconsistency",{"key":184,"text":251},"The write is applied to the cache and propagated to the database as part of the same operation","Write-through keeps cache and store consistent by writing to both synchronously. Option (a) describes write-behind (write-back), and (b) is how a cache-aside setup typically behaves on writes.",{"fields":254,"seniorities":424,"interview_shapes":425,"locales":430,"oauth":432,"question_count":435,"coach_enabled":436,"jd_match_enabled":436},[255,266,286,303,327,340,359,378,398,405,411,418],{"key":5,"name_tr":6,"name_en":6,"sort":171,"specializations":256},[257,260,261,262,263,264,265],{"key":258,"name":259,"field":5},"general","Genel",{"key":154,"name":155,"field":5},{"key":166,"name":167,"field":5},{"key":157,"name":158,"field":5},{"key":150,"name":151,"field":5},{"key":160,"name":161,"field":5},{"key":163,"name":164,"field":5},{"key":267,"name_tr":268,"name_en":268,"sort":215,"specializations":269},"frontend","Frontend",[270,271,274,277,280,283],{"key":258,"name":259,"field":267},{"key":272,"name":273,"field":267},"javascript","JavaScript",{"key":275,"name":276,"field":267},"typescript","TypeScript",{"key":278,"name":279,"field":267},"react","React",{"key":281,"name":282,"field":267},"vue","Vue",{"key":284,"name":285,"field":267},"angular","Angular",{"key":287,"name_tr":288,"name_en":288,"sort":289,"specializations":290},"fullstack","Fullstack",3,[291,292,293,294,295,296,297,298,299,300,301,302],{"key":258,"name":259,"field":287},{"key":154,"name":155,"field":5},{"key":166,"name":167,"field":5},{"key":157,"name":158,"field":5},{"key":150,"name":151,"field":5},{"key":160,"name":161,"field":5},{"key":163,"name":164,"field":5},{"key":272,"name":273,"field":267},{"key":275,"name":276,"field":267},{"key":278,"name":279,"field":267},{"key":281,"name":282,"field":267},{"key":284,"name":285,"field":267},{"key":304,"name_tr":305,"name_en":305,"sort":306,"specializations":307},"devops-cloud","DevOps \u002F Cloud",4,[308,309,312,315,318,321,324],{"key":258,"name":259,"field":304},{"key":310,"name":311,"field":304},"aws","AWS",{"key":313,"name":314,"field":304},"gcp","GCP",{"key":316,"name":317,"field":304},"azure","Azure",{"key":319,"name":320,"field":304},"kubernetes","Kubernetes",{"key":322,"name":323,"field":304},"terraform","Terraform",{"key":325,"name":326,"field":304},"linux","Linux",{"key":328,"name_tr":329,"name_en":329,"sort":330,"specializations":331},"ai-engineer","AI Engineer",5,[332,333,334,337],{"key":258,"name":259,"field":328},{"key":166,"name":167,"field":328},{"key":335,"name":336,"field":328},"llm-rag","LLM\u002FRAG",{"key":338,"name":339,"field":328},"mlops","MLOps",{"key":341,"name_tr":342,"name_en":343,"sort":344,"specializations":345},"database","Veritabanı","Database",6,[346,347,350,353,356],{"key":258,"name":259,"field":341},{"key":348,"name":349,"field":341},"postgresql","PostgreSQL",{"key":351,"name":352,"field":341},"mysql","MySQL",{"key":354,"name":355,"field":341},"mongodb","MongoDB",{"key":357,"name":358,"field":341},"redis","Redis",{"key":360,"name_tr":361,"name_en":362,"sort":363,"specializations":364},"mobile","Mobil","Mobile",7,[365,366,369,372,375],{"key":258,"name":259,"field":360},{"key":367,"name":368,"field":360},"ios-swift","iOS (Swift)",{"key":370,"name":371,"field":360},"android-kotlin","Android (Kotlin)",{"key":373,"name":374,"field":360},"flutter","Flutter",{"key":376,"name":377,"field":360},"react-native","React Native",{"key":143,"name_tr":379,"name_en":144,"sort":380,"specializations":381},"Güvenlik",8,[382,383,386,389,392,395],{"key":258,"name":259,"field":143},{"key":384,"name":385,"field":143},"appsec","AppSec",{"key":387,"name":388,"field":143},"offensive-pentest","Offensive \u002F Pentest",{"key":390,"name":391,"field":143},"cloud-security","Cloud Security",{"key":393,"name":394,"field":143},"devsecops","DevSecOps",{"key":396,"name":397,"field":143},"blue-team-incident","Blue Team \u002F Incident",{"key":399,"name_tr":400,"name_en":401,"sort":402,"specializations":403},"qa-test-automation","QA \u002F Test Otomasyonu","QA \u002F Test Automation",9,[404],{"key":258,"name":259,"field":399},{"key":406,"name_tr":407,"name_en":407,"sort":408,"specializations":409},"data-engineer","Data Engineer",10,[410],{"key":258,"name":259,"field":406},{"key":412,"name_tr":413,"name_en":414,"sort":415,"specializations":416},"game-dev","Oyun Geliştirme","Game Development",11,[417],{"key":258,"name":259,"field":412},{"key":419,"name_tr":420,"name_en":420,"sort":421,"specializations":422},"ml-engineer","ML Engineer",12,[423],{"key":258,"name":259,"field":419},[14,15,16],{"junior":426,"mid":428,"senior":429},{"questions":427,"median_sec":3},20,{"questions":427,"median_sec":3},{"questions":427,"median_sec":3},[431,10],"tr",[433,434],"google","github",21750,true]