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This article explains common MySQL index‑inefficiency scenarios—including left‑most prefix violations, range queries, functions, LIKE patterns, OR/IN misuse, and ORDER BY—provides concrete SQL examples, visual illustrations of B+‑tree indexing, and practical tips such as index jump scans, ICP, and query rewriting to ensure optimal index usage.
This article walks through a real‑world MySQL deep‑pagination incident, detailing the timeline, root‑cause analysis, and multiple optimization techniques—including ID‑based queries, sub‑queries, and cursor pagination—that ultimately stabilized the system and eliminated slow‑SQL overload.
This article explains how to execute two dependent tasks in parallel using CompletableFuture, why @Async and @Transactional are insufficient for multithreaded transaction consistency, and provides a programmatic solution that copies Spring transaction resources between threads to guarantee atomic commit or rollback across asynchronous operations.
This guide explains the fundamentals of state machines, introduces the four core concepts, shows how to model order transitions with diagrams, and provides a complete Spring Statemachine implementation—including database schema, enums, configuration, persistence, controller, service, listeners, testing, and advanced error‑handling techniques—so developers can create reliable, persisted workflows in Java.
Bean Searcher and MyBatis Plus both enable dynamic queries in Java, but they differ in ORM dependence, query syntax, operator flexibility, logical grouping, multi‑table support, and ideal use cases, with Bean Searcher offering dynamic operators and one‑line controller code while MyBatis Plus excels in transactional operations.
This article explains the design and implementation of a business operation logging feature in a Spring Boot application, contrasting flawed hard‑coded approaches with a clean AOP‑based solution, and provides full code snippets, configuration, database schema, and testing tips.
This guide explains how to add two‑factor authentication to a Spring Security‑based Java web application using Google Authenticator, Authy, or a custom TOTP module, covering configuration, code implementation, and testing procedures.
This article presents sixteen practical Spring Boot best‑practice recommendations—including custom BOM management, auto‑configuration, project initialization, code organization, dependency injection, concurrency handling, externalized configuration, logging, testing, and more—to help developers build robust, maintainable microservices efficiently.
This article explores how Lombok’s auto‑generated getter/setter methods can conflict with MyBatis property naming conventions and cause null values, examines the underlying reflection logic in MyBatis, and also reveals why the @Accessor(chain=true) annotation disrupts EasyExcel’s CGLIB‑based mapping, offering practical solutions.
This article explains Redis’s primary roles as a high‑speed cache, in‑memory database, and analytics engine, compares it with relational databases, details its data structures, single‑threaded performance, persistence options, expiration and eviction policies, distributed lock implementation, and strategies for cache penetration, breakdown, and avalanche.
