This guide lists the twenty most frequent pitfalls that new operations engineers encounter, explains why they happen, and provides step‑by‑step safe practices, code examples, risk classifications and a verification checklist to help prevent costly outages and data loss.
The article analyzes why traditional LIMIT/OFFSET pagination fails when data is split across multiple databases, presents a global query approach with its trade‑offs, and proposes an optimized "no‑skip" method plus practical tips using ShardingSphere and Elasticsearch.
Fifteen years after an internship at Nanda Tongyong, the author returns as an external expert to reflect on personal growth, the evolution of the GBase product line—from the early MPP database to AI‑native HTAP solutions—highlighting technical innovations, benchmark results, and the broader impact on the domestic database ecosystem.
The article traces how low‑level programming harnesses—from ENIAC wiring and punch‑card code to assembly, compilers, operating systems, database optimizers, and memory‑management techniques—have been progressively abstracted away by tools, type systems, and language semantics, highlighting what has been "eaten" and what still requires manual expertise.
When network timeouts or retries cause the same payment request to be processed multiple times, duplicate requests become a common failure mode in distributed systems; this article explains five practical idempotency strategies—unique DB indexes, token checks, state machines, Redis SETNX, and downstream dedup tables—and offers guidance on choosing the right approach.
Dolt is an open‑source, MySQL‑compatible database that embeds Git’s version‑control model, letting you commit, branch, merge and audit table data just like source code, with simple installation, CLI commands, SQL stored procedures, GitHub remote support, and CI integration.
This article offers a comprehensive 2026 overview of Redis commands, organized by function, with clear usage examples, return values, performance notes, and best‑practice recommendations such as avoiding KEYS in production and using SCAN, making it a practical reference for developers and architects.
The article explains why dirty data appears in API automation tests, outlines five practical cleanup strategies—including teardown, setup, transaction rollback, unique ID isolation, and data‑factory soft deletes—and provides a complete Pytest‑based Python implementation with code examples and special‑case handling to keep test environments clean and reliable.
The article argues that a 100% accuracy claim for Text2SQL is misleading without considering stability, coverage, and pass‑rate metrics, and it details a deterministic NLQ pipeline that converts natural language to a verifiable intermediate format before rule‑based SQL compilation.
This article provides a detailed walkthrough of the 15 most commonly used Redis commands—including key, hash, list, set, sorted‑set, and monitoring operations—showing syntax, return values, typical use cases, performance characteristics, and cautions for production environments.
The article explains why many developers stuck with MySQL should consider PostgreSQL, highlighting its superior SQL standards support, MVCC concurrency, rich indexing, JSONB performance, full‑text search, extensive extensions, and practical installation and Java integration steps, while also comparing pros, cons, and ideal use cases.
The fourth national security and reliability test released on May 26, 2026 lists 23 certified database products, highlighting a surge in Level II certifications, the entry of time‑series NoSQL databases, and a diversification of vendors—including telecom and fintech players—signaling a major shift in China's domestic database market.
SQLite, the server‑less, single‑file database engine, is the most widely deployed database on the planet, powering Android, iOS, browsers and countless desktop apps; this article walks through its core features, Linux installation, command‑line CRUD, language bindings for Python, C, Java and Go, plus practical backup and performance tricks.
The 2026 XCOPS Intelligent Operations Conference in Guangzhou gathered leading scholars, industry experts, and technology innovators to explore AI‑driven operational upgrades, database intelligence, cloud‑native observability, and multi‑agent architectures, with detailed talks, case studies, and practical roadmaps shared by speakers from academia, finance, and major tech firms.
The article analyzes why duplicate consumption is inevitable in MQ systems, defines message idempotency, and presents four practical solutions—including Redis SETNX, database unique indexes, state‑machine with optimistic locking, and global unique constraints—along with their pros, cons, and best‑practice guidelines for SpringBoot applications.
A veteran Java developer took a 5‑wan‑yuan retail project, relied on an end‑to‑end AI code generator for a month, then faced chaotic project structures, security flaws, and massive refactoring before discovering FeiSuan JavaAI's multi‑agent workflow that finally turned the disaster into a deliverable.
This article presents thirty practical SQL optimization tips, covering index usage, avoiding full‑table scans caused by operators like !=, NULL checks, OR, LIKE, IN, functions, and expressions, as well as best practices for temporary tables, cursors, and transaction size to improve database performance.
The article explains the causes of duplicate requests in distributed systems, defines idempotency, and presents eight concrete implementation strategies—including token mechanisms, unique database indexes, optimistic and pessimistic locks, distributed locks, state machines, request serial numbers, and MQ‑based handling—each with code samples, advantages, drawbacks, and usage guidelines.
This article walks through the rationale, common functions, and real‑world case studies of storing and querying JSON columns in a relational database, exposing issues with null handling, batch updates, and dynamic SQL generation, and presents step‑by‑step debugging and robust solutions.
This article explains why MySQL deadlocks occur, shows how to enable and read deadlock logs, walks through three real‑world case studies, and provides practical SQL, configuration, and architectural solutions to resolve and prevent deadlocks in production environments.
ScopeDB introduces a cloud‑native, real‑time analytics database that combines structured core columns with a flexible JSON column, adaptive indexing, a custom query language (ScopeQL), and true compute‑storage separation, delivering sub‑second query latency, high throughput, and up to 70% cost reduction compared with traditional big‑data stacks.
This article walks you through a systematic, step‑by‑step process for diagnosing and fixing MySQL CPU usage spikes—from identifying the symptoms and gathering system metrics, to pinpointing problematic queries, analyzing locks and buffers, applying index and configuration tweaks, and validating the performance gains with real‑world examples and command‑line tools.
This article compiles a curated list of production‑ready Go packages covering testing, logging, error handling, caching, databases, HTTP routing, HTTP clients, fault tolerance, Kafka, and various utility libraries, explaining their key features, concrete code examples, and why they are preferred in real‑world services.
The article argues that relying on many specialized databases creates operational complexity, higher costs, and maintenance overhead, while PostgreSQL’s extensible ecosystem—offering full‑text search, vector, time‑series, JSONB, and more—delivers comparable or superior algorithms, proven performance, and a simpler, more reliable stack for the vast majority of use cases, especially in AI applications.
The article argues that for typical file‑upload scenarios you should upload to MinIO first and then write to the database without trying to enforce strong distributed consistency, explaining the pitfalls of transaction‑based solutions and offering simple async cleanup strategies.
When sharding databases, independent auto‑increment IDs can collide, causing data integrity issues; this article explains why the conflict occurs and walks through five practical solutions—including UUID, custom auto‑increment steps, segment mode, Snowflake, and Meituan Leaf—detailing their trade‑offs, performance, and implementation steps.
IntelliJ IDEA already covers about 80% of development needs, but its rich plugin ecosystem lets you fine‑tune your workflow like a custom Vim setup; this article reviews essential plugins—including AceJump, Catppuccin Theme, CodeGlance Pro, Edit‑Tabs‑Location, GenerateAllSetter, GitHub Copilot, Inspection Lens, MyBatis Log Free, Power Mode II, IdeaVim, and Rainbow Brackets—detailing core features, configuration tips, and trade‑offs to help you choose wisely.
This article outlines a comprehensive, risk‑controlled SOP for migrating business data—including model changes, storage shifts, incremental dual‑write, back‑filling, full and incremental consistency checks, read‑switching, and final decommissioning—backed by concrete SQL examples and visual diagrams.
This step‑by‑step guide shows how to create a natural‑language database query assistant using Dify by preparing a test MySQL database, creating a read‑only user, installing the Dify database plugin, configuring the connection, building an Agent with a strong SQL‑capable LLM, setting prompts, adding Text‑to‑SQL and SQL‑Execute tools, testing simple, filtered and aggregate queries, and finally extending to multi‑table scenarios.
This article explains why naïve per‑record inserts or updates in SpringBoot cause severe performance problems, analyzes three common mistakes, and demonstrates how MyBatis batch processing—through connection reuse, prepared‑statement reuse, and batch transaction commits—can speed up operations by tens of times, with practical code examples and configuration tips for handling millions of rows.
This article explains the shift from Redis's traditional single‑threaded model to the multithreaded I/O architecture introduced in Redis 6.0, detailing core design principles, performance benchmarks, Go code simulation, interview questions, and practical tuning tips for high‑concurrency workloads.
This guide walks you through identifying why MySQL CPU usage jumps, from confirming the MySQL process consumes CPU to checking connection counts, slow queries, lock waits, configuration settings, and business‑level traffic, and then provides short‑term mitigations and long‑term solutions such as read‑write splitting, sharding, and caching.
This article provides a comprehensive analysis of Redis persistence mechanisms—including RDB snapshots, AOF append‑only logs, and the hybrid RDB+AOF mode—covering their architectures, trigger methods, performance trade‑offs, rewrite processes, interview‑focused questions, and practical recommendations for production environments.
The Chinese database sector has moved beyond the question of whether domestic products exist to a fierce survival race where legacy system weight, migration engineering, and ecosystem strength determine which vendors can become lasting, cloud‑native, and AI‑ready infrastructure assets.
An online payment service suffered invisible data loss and lock timeouts because a newly deployed business branch failed to commit its transaction, leading to polluted connections that were reused by other services, and the article explains the root cause, debugging steps, code fixes, and preventive measures.
This article analyzes JD's self‑developed database kernel DongSQL, describing its architecture, the challenges of overload, flash‑sale write spikes, cache consistency, execution‑plan drift, and thread congestion, and explains how hint‑based limiting, RETURNING syntax, statement outlines, and a built‑in thread pool address each issue.
The article explains how Java 26’s native support for RFC 9562 UUIDv7 provides an ordered, unique, and standards‑compliant distributed identifier, compares it with traditional UUIDs and Snowflake, shows the new API usage, highlights hidden pitfalls, and offers practical best‑practice guidelines for production deployment.
Random UUID primary keys cause severe B‑tree write performance degradation due to low cache locality, while the new UUIDv7 format embeds timestamps for sortable, efficient inserts, and JDK 26 introduces a native API to generate them, offering a practical solution for Java back‑ends.
A mysterious payment failure where orders appeared successful but were never persisted was traced to a missing transaction commit in a special code path, leading to polluted connections that silently broke subsequent transactions, and the article explains the root cause, debugging steps, fix, and preventive measures.
This article presents a comprehensive guide to 16 practical Redis use cases—including caching, distributed locks, global IDs, counters, rate limiting, bitmaps, shopping carts, timelines, message queues, lotteries, likes, product tagging, filtering, follow‑recommendation models, and ranking—complete with code snippets and data‑structure examples.
This article experimentally compares MySQL JOIN and IN (separate queries) across small, medium, and large data sets, providing PHP benchmark code, performance results, and practical conclusions on when each approach is more efficient.
In 2026 the database ecosystem faces fierce competition between MySQL and PostgreSQL, while AI emerges as a new driver prompting open‑source projects like AliSQL to release DuckDB, vector engines and intelligent CLI, reshaping how relational databases serve both transactional and analytical workloads.
An online payment outage was traced to a forgotten transaction commit in a Spring service, leading to polluted connections that silently blocked subsequent orders, and the article explains the root cause, debugging steps, quick fix, and preventive measures to avoid similar bugs.
This article analyzes the severe replication‑delay issues in MySQL master‑slave setups, identifies four typical workload patterns that cause lag, demonstrates how AliSQL's AI assistant pinpoints the root causes, and explains the kernel‑level optimizations that completely remove the delay.
This article breaks down Redis performance limits, showing that a single node can handle roughly 100‑200k simple GET/SET QPS and up to 500‑700k with multithreaded I/O, while sharded clusters can theoretically reach millions of QPS, though practical factors affect the actual throughput.
Google’s newly released Room 3.0 Alpha marks a landmark rewrite that transforms the Android‑only persistence library into a Kotlin Multiplatform solution, introducing package renaming, KSP‑only processing, coroutine‑first APIs, and experimental web support, while providing detailed migration steps and new features such as custom DAO return types.
This article reviews the Qoder JetBrains plugin, explaining its memory‑perception and dual‑engine architecture, detailing installation steps, showcasing an end‑to‑end Spring Boot voting app generated by the AI, and discussing model choices and practical benefits for Java developers.
This article explains how to store and query extensible JSON columns in a MySQL‑based system, lists the most useful JSON functions, walks through several real‑world scenarios—including dynamic extension queries and weight‑management cases—identifies subtle bugs caused by null values, and presents step‑by‑step SQL and MyBatis fixes to ensure reliable batch updates.
A newcomer replaced MyBatis with MyBatis‑Plus in an old MySQL‑based project, encountered a "Conversion not supported for type java.time.LocalDateTime" error, traced it to MyBatis 3.5.1 dropping built‑in type handling and an outdated mysql‑connector‑java driver, and resolved it by upgrading the driver while also fixing a related validation bug that caused production failures.
This article explains why using SELECT * does not automatically invalidate MySQL indexes, explores common scenarios that cause index loss such as left‑most prefix violations, function calls, implicit type conversions, wildcard LIKE patterns, OR/IN/NOT IN misuse, and ORDER BY pitfalls, and provides practical optimization recommendations with concrete SQL examples and verification methods.
The article examines why traditional manual or full‑backup test data creation becomes a performance bottleneck in modern micro‑service, TB‑scale environments, identifies three structural imbalances—data‑dependency, generation‑logic, and semantic redundancy—and presents a three‑layered optimization framework plus engineering best‑practices that can cut data‑prep time by up to 68%.
This article explains how Lance's Python API creates scalar and vector indexes, walks through the internal Rust implementation of the create_index workflow, and details the transaction, commit, and error‑handling mechanisms that ensure atomic and consistent index creation.
This guide explains why MySQL replication lag spikes, how to distinguish IO‑thread pull problems from SQL‑thread apply bottlenecks, provides step‑by‑step commands, configuration examples, real‑world case studies, best‑practice recommendations, and monitoring setups to reliably troubleshoot and prevent replication delays.
While many believe that using SELECT * inevitably disables indexes, MySQL’s optimizer only skips indexes when a full table scan is cheaper, and patterns such as violating the left‑most prefix, applying functions or implicit casts, leading‑wildcard LIKE, OR/IN misuse, and mismatched ORDER BY can cause index invalidation, prompting some companies to forbid SELECT * in production.
Illia Polosukhin, one of the authors of the Transformer paper, rewrote OpenClaw in Rust as IronClaw, adding multiple security layers, a database‑backed memory system, WASM sandboxing, encrypted credential storage, and extensible agent components to make AI agents both safe and efficient.
An online payment service failed when a newly added business logic forgot to commit its transaction, leaving a polluted connection that silently blocked subsequent orders, and the post‑mortem explains the root cause, debugging steps, code fixes, and preventive measures.
This article walks through practical techniques for designing a highly concurrent Python backend that stays stable under load, covering architecture planning, async programming, load balancing, database scaling, distributed tasks, caching, rate limiting, monitoring, and graceful shutdown.
The article examines the long‑awaited Go proposal to add a crypto/uuid package, explains UUID version history, the design choices behind the minimal API, why only V4 and V7 are provided, and how developers can smoothly migrate from the third‑party google/uuid library.
This article breaks down the essential technical and soft‑skill competencies—ranging from deep Linux kernel knowledge and database optimization to cloud‑native Kubernetes expertise, observability, automation, cost‑saving architecture, and security—that distinguish high‑salary operations engineers and provides a practical roadmap for achieving them.
This guide explains the advantages of using PDO instead of mysqli for PHP database connections, walks through MySQL and PostgreSQL setup with detailed code examples, recommended configuration options, and a checklist for troubleshooting common connection errors.
A recent production incident revealed that a forgotten transaction commit in one service left a database connection polluted, causing unrelated payment requests to fail silently, and the article walks through the root cause, debugging steps, code fixes, and preventive measures.
A payment service showed successful orders but no data in the database, leading to lock timeouts; the root cause was a hidden missing commit in a special code path that polluted the connection pool, causing other services to inherit an uncommitted transaction and fail intermittently.
A payment service failed to insert orders despite successful payments, showing no errors, occasional lock timeouts, and intermittent success, which was traced to a missing transaction commit that polluted reused connections, causing unrelated business failures until the bug was fixed and preventive measures were added.
The article details Du Xiaoman's 2023 campus hiring salaries for Java backend roles, explains the significance of signing bonuses, shares a successful intern story, and provides in‑depth interview preparation covering thread pools, locks, AQS, CAS, SQL optimization, sharding, MVCC, and transaction isolation levels.
This guide walks through installing MySQL on Windows, Linux and macOS, configuring security settings, creating the first database and tables, and demonstrates basic queries, updates and deletions with concrete command‑line examples.
This article explains the common reasons Spring transactions become ineffective or fail to roll back—such as wrong method visibility, final modifiers, self‑invocation, non‑Spring beans, multithreading, unsupported table engines, misconfigured propagation, swallowed exceptions, and improper rollback settings—while providing practical code solutions and best‑practice recommendations.
This article introduces a generic asynchronous processing SDK for Java back‑ends, explaining its design principles, advantages, component architecture, database schema, configuration via Apollo, usage steps, and practical demonstrations, while providing complete code snippets and a GitHub repository for reference.
MySQL 9.6 shifts foreign‑key checks and cascade handling from the InnoDB storage engine to the SQL engine, eliminating hidden changes, improving binary‑log visibility, and delivering full‑log replication and analytics without sacrificing performance.
The article argues that the SaaS model is collapsing as AI agents can replace traditional front‑end, back‑end, and middleware layers, driving a shift toward a simple Agent + Database architecture, reviving CLI tools, and redefining the role of GUIs in the era of large language models.
This guide explains how to integrate the PostGIS spatial extension into a Kingbase database running in Docker, covering prerequisite communication with support, extracting the extension files, copying necessary binaries, restarting the container, and verifying the installation with sample queries.
This article examines the double‑write consistency problem between databases and caches like Redis, explains why naïve cache‑first or DB‑first updates can cause stale or phantom data under high concurrency, and evaluates four practical solutions with detailed trade‑offs and recommended retry mechanisms.
This guide shows how to use PHP's mysqli_num_rows function to obtain the number of rows returned by a MySQL query, including connection setup, error handling, executing a SELECT statement, retrieving the count, and important considerations when the query fails.
MySQL 9.6.0 introduces a modular audit log system, GTID replication overhaul, InnoDB enhancements, hardened security components, richer JSON view controls, logging upgrades, Shell extensions, and numerous bug fixes, all aimed at improving performance, flexibility, and enterprise‑grade reliability.
The article details a step‑by‑step migration from MyBatis 3.5.0 to MyBatis‑Plus 3.1.1, explains why the conversion error for java.time.LocalDateTime appears after the switch, shows how to trace the root cause through stack traces, upgrades the mysql‑connector‑java to 5.1.37 (and later 5.1.42) to resolve the issue, and shares broader lessons about component upgrades and unexpected bugs.
The article details a MySQL kernel‑level merged‑seckill optimization that replaces traditional queue‑based flash‑sale handling, achieving up to 5.5× higher TPS (up to 23,543 TPS on 128 threads) and sustaining 1.5W+ orders per second, while remaining transparent to applications and preserving compatibility with existing SQL.
This guide shows how to set up MySQL InnoDB ReplicaSet, start MySQL Router 8.2, configure read/write split routing, and verify that reads are directed to replicas while writes go to the primary instance, all without modifying application code.
This article explains MySQL transaction fundamentals, illustrates a banking transfer scenario, details the ACID properties, explores dirty reads, non‑repeatable reads and phantom reads, and compares the four SQL‑92 isolation levels with practical code examples and InnoDB behavior.
This guide enumerates frequent misconceptions in SQL performance—from over‑indexing and SELECT * misuse to improper transaction handling and outdated monitoring practices—explains why they hurt efficiency, and provides concrete, version‑aware solutions to optimize queries, schema design, and database operations.
This guide explains why InnoDB fuzzy queries lose indexes, introduces MySQL full‑text search with inverted indexes, shows how to create and use full‑text indexes via CREATE TABLE and ALTER statements, and demonstrates natural language, boolean, and query‑expansion modes with practical SQL examples.
The MySQL Server repository on GitHub has seen no code commits for over three months, sparking concerns about Oracle's strategic shift, recent large‑scale layoffs, and the future sustainability of the community‑driven open‑source database.
This article explains how MySQL implements indexes with B+Tree structures, why they outperform full table scans, the internal layout of leaf and internal nodes, insertion and split mechanics, range‑query processing, and practical optimization tips for clustered and secondary indexes.
When MySQL replication falls behind, common culprits include oversized buffer pools, backup‑induced MDL waits, large transactions, slow queries, parallel replication quirks, and network issues, and this guide offers concrete configuration adjustments to restore sync and improve performance.
This article walks through a series of practical backend techniques—batch processing, asynchronous execution, caching, pre‑processing, pooling, parallelization, indexing, transaction management, pagination, and lock granularity—to dramatically reduce API response times from several seconds to just a few milliseconds.
This article explains the fundamental differences between DELETE, TRUNCATE, and DROP, covering interview expectations, underlying mechanisms, performance impacts, transaction safety, best‑practice usage scenarios, and common pitfalls to help candidates choose the right command for any database task.
This article details a Redis bucket‑based inventory deduction architecture that guarantees strong consistency while eliminating over‑sell and under‑sell, boosting hot‑spot deduction TPS and stability through a merge‑commit process and comprehensive module design.
This guide presents a comprehensive collection of essential MySQL commands, covering connection management, database creation and selection, table definition and alteration, CRUD operations, query optimization techniques, performance monitoring, and user permission handling, providing clear examples for each command.
This community roundup reviews the 2025 release of the SCALE open‑source LLM‑SQL benchmark, SQLE platform updates, curated video playlists, a curated list of the year's ten best database articles, and provides reference links for further exploration.
This article breaks down Redis's nine data types, explains the underlying structures and typical scenarios for each, compares best‑practice usage, highlights interview focus points, and warns about common misconceptions to help developers choose the most efficient storage solution.
An in‑depth post‑mortem of a real Go microservice outage reveals how committing a DB transaction before publishing a RabbitMQ event caused duplicate charges, and demonstrates how adopting the Transactional Outbox pattern restores atomicity, prevents ghost bugs, and improves reliability.
This article explains how Redis master‑slave replication provides hot backup, read‑write separation, high availability, and horizontal scaling by detailing its three‑stage workflow, full and partial synchronization mechanisms, key configuration options, and practical analogies for clear understanding.
This guide shows how to connect to a MySQL database in PHP, execute a SELECT query, and use the mysqli_num_rows function to obtain the number of rows returned, including error handling and proper connection closure.
The article examines how PostgreSQL’s latest pgvector 0.8.0 release adds iterative index scans and smart query planning, enabling fully free vector search within an existing relational database, compares performance, cost, and architecture against dedicated vector databases like Pinecone, and outlines migration steps and best‑practice guidelines.
This tutorial walks through MySQL table joins—INNER, LEFT, RIGHT, and FULL OUTER—using clear diagrams, step‑by‑step SQL examples, and sample data, helping readers understand each join type, its result set, and how to emulate full outer joins in MySQL 5.7.
This article analyzes MyBatis-Flex, highlighting its lightweight, flexible, and powerful design, compares its feature set and performance against MyBatis-Plus and Fluent-MyBatis, lists supported databases, and provides a step‑by‑step quick‑start guide with code examples for Spring Boot integration.
To reliably handle RocketMQ's at-least-once delivery semantics, this guide explains why duplicate consumption is inevitable, outlines three defensive layers—Redis‑based idempotency, database unique constraints, and state‑machine checks—provides production‑grade Java code, and details ACK/retry strategies and monitoring practices for robust systems.
MyBatis-Flex is a lightweight, high-performance MyBatis enhancement offering flexible CRUD, advanced QueryWrapper, extensive database support, and benchmarked speeds up to ten times faster than MyBatis-Plus, with a step-by-step quick-start guide covering table creation, Maven setup, Spring Boot configuration, entity mapping, and usage examples.
This article walks through the strengths, typical use cases, and Python connection code for relational databases (MySQL, PostgreSQL, SQLite), NoSQL stores (MongoDB, Redis, Neo4j), cloud‑native options (DynamoDB), and emerging vector databases such as Milvus, helping you decide which fits your project.
Rudis v0.2.0 introduces a major architecture overhaul, upgraded Tokio runtime, shared‑nothing threading, master‑slave replication, transaction support, and a refactored KEYS command that boosts performance by up to 99.55% for large data sets.
This comprehensive guide explores MySQL’s layered architecture, core components, storage engines, and detailed SQL language structures, while providing practical commands, optimization techniques, security best practices, and operational procedures for administrators to efficiently manage, tune, and secure MySQL databases.
This article introduces Yii Database 2.0—a modernized PHP database abstraction layer with new drivers, enhanced type safety, and powerful features—then walks through Composer installation, basic connection setup, and practical query, insert, and transaction examples.
