This tutorial walks SQL newcomers through the three essential database commands—creating a database, listing all databases, switching to a specific one, and safely dropping a database—providing copy‑paste code, practical scenarios, and beginner‑focused pitfalls.
This comprehensive guide walks MySQL administrators through the fundamentals of backup and recovery, covering RPO/RTO concepts, tool comparisons (mysqldump, mydumper, xtrabackup), step‑by‑step scripts for full, incremental, and binlog backups, encryption, compression, troubleshooting, and best‑practice monitoring to ensure data safety and rapid restoration.
Oracle announced MySQL 9.7.0 LTS, the first major LTS since 8.4, introducing community‑available enterprise features such as the Hypergraph optimizer, dynamic data masking, enhanced replication observability, and new operational tools, while addressing community concerns about Oracle’s commitment and recent development slowdown.
When MySQL CPU usage spikes above 80% or hits 100%, this guide walks you through a systematic investigation—from confirming the MySQL process consumes CPU, checking system and MySQL status, analyzing connection counts, slow queries, lock waits, and configuration settings, to applying short‑term mitigations and long‑term architectural fixes.
A seasoned DBA recounts a 3 AM MySQL outage caused by an unindexed query, then shares practical strategies for indexing, connection‑pool sizing, slow‑query tuning, replication lag handling, monitoring, automation, performance tuning, security hardening, and future‑proofing MySQL deployments.
This article examines why adding a column to a MySQL table with tens of millions of rows can lock the table, then presents six practical solutions—including native online DDL, PT‑OSC, gh‑ost, dual‑write migration, maintenance downtime, and partition sliding‑window—detailing their procedures, trade‑offs, and suitable scenarios.
This guide equips MySQL ops engineers with practical DML/DQL commands, permission management, transaction handling, and common pitfalls, offering step‑by‑step examples, performance tips and safety checklists to ensure reliable database maintenance and troubleshooting.
This article walks MySQL DBAs through common MySQL InnoDB Cluster fault scenarios—node restarts, crashes, network partitions, and full‑cluster reboots—providing step‑by‑step commands, status outputs, recovery actions, and impact analysis to ensure high availability and data safety.
When adding a column to a MySQL table with tens of millions of rows, lock contention can cripple services, so this guide compares six practical solutions—including native online DDL, PT‑OSC, gh‑ost, partition sliding windows, downtime maintenance, and dual‑write migration—detailing their mechanisms, trade‑offs, use‑cases, and step‑by‑step commands to ensure minimal disruption.
This article examines the architecture of AI agents, compares fully autonomous task planning with human‑crafted planning in Alibaba Cloud's RDS AI Assistant, presents real‑world accuracy data, and proposes a hybrid, case‑library‑driven approach to achieve reliable, explainable, and repeatable database operations.
This article recounts a 3 AM MySQL outage, analyzes its root causes, and shares comprehensive operational strategies—including index optimization, connection‑pool tuning, slow‑query fixing, replication lag handling, monitoring metrics, automation scripts, performance tuning, security hardening, and future trends—to help DBAs prevent and resolve similar incidents.
This article explores how integrating AI‑driven AIOps with the TiDB distributed database can automate monitoring, enable proactive anomaly detection, streamline root‑cause analysis, and optimize capacity planning, ultimately shifting database operations from manual firefighting to intelligent, data‑driven management.
This guide explains how integrating large language models with MySQL can transform traditional database management by enabling intelligent fault diagnosis, automatic SQL optimization, knowledge‑base updates, and a complete monitoring‑optimization feedback loop, complete with implementation steps, code samples, and best‑practice recommendations.
The article explains how Baidu Cloud Redis's Data Flashback feature combines RDB snapshots with timestamped AOF logs to provide fast, space‑efficient, point‑in‑time data recovery, overcoming the limitations of native Redis persistence in high‑traffic scenarios.
The article summarizes Lai Kunchi's presentation at the 24th GOPS Global Operations Conference, covering the current state and challenges of database development, Guangdong Mobile's database operation system, and future directions for managing heterogeneous databases in evolving business architectures.
This article explains how to use PHP's mysqli_num_rows function to retrieve the number of rows in a MySQL result set, providing a complete example that connects to a database, executes a query, checks for errors, obtains the row count, and outputs it.
This article explains how to handle MySQL disk‑space alerts by using the pt‑online‑schema‑change (pt‑osc) tool to selectively retain needed rows, migrate data to a temporary table, and drop the original table, thereby achieving fast, low‑impact data cleanup.
To handle growing memory pressure across thousands of Redis servers, the platform implements an automated, daily resource‑balancing scheduler that selects overloaded hosts, chooses optimal nodes based on instance count, tier, and placement rules, then safely migrates them through a multi‑step process with rigorous validation.
This guide walks through accessing a production TiDB cluster via pod IP, Service ClusterIP, or DNS, initializing users and databases, and performing scaling and version upgrades by editing the cluster's YAML configuration in Kubernetes.
This article explains TiDB’s distributed relational database architecture, compares Kubernetes‑based and physical‑machine deployments, and describes Zhihu’s platform‑driven approach—including TiDB Operator, TiUP, self‑service tooling, monitoring, backup, security, and FinOps—to enable efficient database management for both developers and DBAs.
This article provides 10 detailed Python code examples demonstrating how to connect to, query, insert, update, delete, and manage MySQL databases with proper error handling and resource management.
This article reviews the evolution of databases and large models, explains vector database fundamentals and RAG pipelines, and details Baidu's VectorDB architecture, performance advantages, and its role in AI‑enhanced database operations.
This article reviews the evolution of databases and large models, explains the role of vector databases and Retrieval‑Augmented Generation (RAG) in AI‑enhanced data management, and showcases Baidu Cloud's VectorDB and DBSC solutions for intelligent database operations and knowledge‑driven services.
This article details a step‑by‑step recovery of a ClickHouse 4‑shard, 3‑replica cluster after a node’s disks failed, covering verification of residual data, Zookeeper metadata cleanup, table reconstruction, distributed table restoration, and validation of synchronization across replicas.
This article details Qunar.com's Redis automation operations system, covering background challenges, the high‑availability cluster architecture, resource management, automated deployment, various migration strategies, scaling mechanisms with RedisGate, inspection processes, and future AI‑driven enhancements.
The paper details Baidu Intelligent Cloud’s design and deployment of a domain‑specific knowledge‑base Q&A system for database operations, combining prompt‑engineered LLMs with hybrid vector‑search using LangChain, BES vector store, and custom ingestion, addressing recall, token limits, and hallucination challenges across dashboard and IM bot interfaces.
This article analyzes why the MariaDB audit plugin crashes on MySQL 5.7, presents compatibility tables before and after source modification, details the verification steps, and provides a step‑by‑step solution including source code changes and recompilation to make the plugin work reliably.
An original case study examines a MongoDB 4.0.14 replica set crash triggered by exceeding the WiredTiger session limit when a primary creates a background index and subsequently drops it, causing blocking on the secondary, leading to connection saturation, session exhaustion, and instance failure.
This article explains what SQL injectors are in MyBatis‑Plus, lists the built‑in extended injectors, shows how to configure them globally, demonstrates custom mapper creation, provides complete code examples and test cases, and guides readers through building their own SQL injector for full‑field updates and batch operations.
The article details Huolala’s comprehensive approach to managing diverse databases across multiple clouds, covering systematic stability engineering, automated SQL governance, Redis and Kafka reliability strategies, cost‑optimization tactics, and the evolving roles of modern DBAs in a complex, high‑scale environment.
This article provides a step‑by‑step guide for scaling an OceanBase cluster, covering both white‑screen and black‑screen methods to add zones (replicas) and resources (OBServers), including configuration file preparation, deployment commands, zone addition, verification queries, and procedures for both expansion and contraction.
This article presents a comprehensive case study of TiDB, an open‑source distributed relational database, detailing its features, architecture, evolution within AutoHome, key business applications such as recommendation pools, financial reporting, and interactive events, as well as the automated operations and troubleshooting practices adopted to ensure high availability and scalability.
This article analyzes ClickHouse distributed DDL execution by presenting typical failure scenarios, dissecting the underlying Zookeeper‑based workflow, and offering practical mitigation steps to avoid DDL timeouts and improve cluster stability for large‑scale data operations.
Bigkeys—Redis values over 1 MB or structures with more than 2,000 elements—cause memory imbalance, command blocking, network overload, and migration failures, so DBAs must detect them using built‑in commands or RDB analysis, split or partition oversized keys, and tune migration settings to preserve performance and availability.
This article walks through a step‑by‑step investigation of why incremental backups failed on a DBaaS platform, revealing that the PERCONA_SCHEMA.xtrabackup_history table’s binlog_pos column was too short, and shows how altering its length resolves the problem.
The article recounts Chen Jianhua’s presentation at the GOPS Global Operations Conference, detailing ZTO’s three‑stage journey in building a database operations platform—from initial automation to self‑service and finally to fine‑grained, data‑driven intelligent management—while sharing lessons and future plans.
The article analyzes a MySQL MGR cluster failover incident caused by a VM pause and system time jump, explains the underlying detection mechanisms, presents detailed source code excerpts, and demonstrates through debugging that time changes alone do not trigger MGR failover.
This article demonstrates how to configure the open-source Orchestrator tool for automatic MySQL cluster failover, explains key parameters, and presents three test cases covering normal failover, lag‑induced prevention, and the effect of disabling global recoveries.
This article walks through the complete process of creating a highly available MySQL master‑master cluster using Docker containers, MySQL replication, and Keepalived for automatic health checks, virtual IP failover, and seamless traffic switching, while also sharing common pitfalls and their solutions.
The article recounts a performance incident on a MongoDB 4.2 sharded cluster where one shard’s CPU spiked to 100% during a mail‑sending test, describes the diagnostic steps using monitoring data, slow‑query logs, and executionStats, and concludes with the root cause and remediation.
The article shares a senior DBA's journey from early database engine development to modern MySQL operations, outlining practical methods for improving efficiency, automating monitoring, building data‑driven processes, and redefining the DBA role for proactive, high‑impact service delivery.
This article details Qunar's implementation of PostgreSQL high‑availability using Patroni, covering solution selection, custom DCS and failover mechanisms, operational impact, comprehensive testing procedures, performance metrics, and future directions for cross‑region HA deployment.
This article explains how MySQL InnoDB partition tables can dramatically boost query speed, simplify routine operations, enable parallel writes, and provide efficient data exchange and cleanup compared to non‑partitioned tables, illustrated with concrete SQL examples and performance metrics.
This article explains how Pika, a disk‑based Redis‑compatible KV store, overcomes Redis’s memory limits with larger capacity, faster backup, and comparable performance, and describes its deployment, management, monitoring, and migration workflows within 360’s HULK cloud platform.
This article documents a real‑world incident where a MyISAM table in a Percona XtraDB Cluster caused data inconsistency and node self‑shutdown, analyzes the root cause, and describes how using pt-online-schema-change together with proper engine conversion restored consistency across the cluster.
This article explains why MySQL 8's clone plugin may report a restart failure (error 3707), analyzes the role of the monitoring process, and provides systemd service configurations—including RestartForceExitStatus=16 and Environment=MYSQLD_PARENT_PID=1—to ensure automatic restarts succeed after clone operations while preventing unwanted restarts in other failure scenarios.
This article explains common causes of Redis latency spikes—including slow commands, large keys, concentrated expirations, memory limits, fork overhead, CPU binding, AOF settings, swap usage, and network saturation—and provides step‑by‑step diagnostic commands and practical mitigation techniques.
This article analyzes how adjusting the MHA ping_interval and enabling secondary_check_script can increase MySQL high‑availability cluster tolerance to network packet loss and corruption, presenting test setups, parameter configurations, log observations, and conclusions on their impact on failover behavior.
This article details a real‑world MySQL production data loss incident, explains how to identify the relevant binlog range, use binlog2sql and MyFlash to generate reverse SQL or binary logs, and outlines the step‑by‑step recovery process and post‑mortem reflections for operations teams.
The article explains how to construct an effective DBA operations team by focusing on reusable infrastructure, clear team standards, a structured training system, a comprehensive knowledge base, and a positive team atmosphere, providing practical tools and methods for each aspect.
This article describes how CTrip tackled rapid Redis cluster growth by moving from vertical scaling to a containerized horizontal splitting approach, then introduced a binlog‑server based horizontal expansion and shrinkage method that reduces operation time, eliminates data migration, supports both scaling up and down, and improves resource utilization.
This article examines how differences between Galera GTID and MySQL GTID caused replication interruptions during a Percona XtraDB Cluster (PXC) split at Qunar, details the migration procedure, reproduces the problem with step‑by‑step commands, explains GTID concepts, and proposes operational improvements to avoid data inconsistency.
This article explains how MySQL transactions behave when a client’s network connection is abruptly lost, why the server does not automatically abort the transaction, and provides practical scripts and configuration tips to detect and kill long‑running idle transactions.
This article analyzes a TiDB cluster performance incident where QPS dropped and duration spiked due to write‑write conflicts, detailing the monitoring data, root‑cause investigation of server‑busy and scheduler latch issues, and the attempted mitigation steps such as enabling txn‑local‑latches and adjusting insert statements.
This article demonstrates how to audit MySQL user actions by configuring init_connect, creating an audit log table, enabling binlog, and analyzing binlog entries to identify the user and IP responsible for accidental table deletions.
This article walks through preparing a four‑node MySQL environment, configuring password‑less SSH, setting up master‑slave replication with GTID, installing and configuring MHA, testing connectivity, running the manager, verifying automatic failover, and highlighting the key advantages of using MHA for high availability.
This article details CTrip's evolution of Redis management—from early single‑instance deployments and custom CRedis client, through automated scaling, containerization with Kubernetes, secondary scheduling algorithms, Intel Optane integration, and hybrid‑cloud deployment—highlighting operational challenges, solutions, and performance outcomes.
The Zhengda Hospital HIS database outage, caused by unauthorized scripts and poor permission controls, sparked a detailed discussion on how to prevent reckless production testing, enforce proper authorization, design efficient yet secure workflows, improve outsourcing oversight, and build robust emergency and compliance practices.
This article examines the severe time‑critical pain points of bank database operations, explains why AI‑based intelligent ops are needed, describes the platform architecture, unsupervised algorithms (3σ, Isolation Forest, DBSCAN, Pearson, Apriori), and presents a real‑world case study that demonstrates anomaly detection, root‑cause analysis, and practical optimization recommendations.
In this interview, a senior database expert from Huaxia Bank shares twelve years of experience and explains how moving from traditional replication to multi‑active, real‑time consistent data centers, combined with automation and mobile remote operations, is transforming banking database reliability and security.
The article outlines practical database selection criteria—cost, stability, performance, scalability, security—and details iQIYI’s concrete implementations of MySQL, Redis, Couchbase, and the custom HiKV store, describing their architectures, backup and scaling mechanisms, operational tooling evolution, and a decision‑tree guide for matching workloads to the appropriate database technology.
The article analyzes a recurring MySQL alarm where over 200 SQL statements are killed per minute due to buffer‑pool latch contention and a near‑90% dirty‑page ratio, then demonstrates how adjusting InnoDB parameters and doubling the buffer‑pool size eliminated the kills and restored performance.
This article explains the need for high‑availability MySQL services, critiques the original in‑house HA approach, and details how the mature MHA framework was extended into WMHA with added VIP monitoring, enhanced failover procedures, richer notifications, and a reorganized deployment structure to improve reliability and reduce DBA intervention.
Bianque, TDSQL’s intelligent operation platform, automatically collects and indexes database metrics, applies a knowledge‑base‑driven analysis engine to diagnose availability, performance and reliability issues, issue risk warnings and optimization recommendations, dramatically cutting DBA effort and support tickets across Tencent’s cloud services.
This article explains how MySQL 8.0 InnoDB handles DDL statements, describes the five classification dimensions (Instant, In‑Place, Rebuild Table, Concurrent DML, Metadata‑only), provides examples of each cost level, and offers operational recommendations for safely applying schema changes.
This article explains how MongoDB's mongos router manages client‑to‑mongos and mongos‑to‑mongod connections, compares the default per‑connection‑per‑thread model with the adaptive thread‑pool introduced in version 3.6, details the internal traditional and ASIO connection pools, relevant configuration parameters, and provides practical guidance on interpreting connection‑pool statistics.
Facing metadata inconsistency, ten‑thousand‑device scale, and the need for intelligent, event‑driven automation, Tencent Cloud Redis’s sole operations lead built a unified DB‑CMDB, a job‑platform for reusable workflows, and AI‑assisted scheduling, transforming DBAs into developer‑operators and driving 300% efficiency gains.
This article examines two MySQL deadlock scenarios under REPEATABLE READ isolation—one with a non‑unique index and another with a unique index—by presenting table definitions, test data, raw deadlock logs, and step‑by‑step analysis of lock acquisition and waiting, ultimately offering practical recommendations to avoid such deadlocks.
This article outlines the evolution from manual MySQL DBA tasks to a fully automated, platform‑based solution at China Mobile’s "Mobile Cloud", detailing standardization, tooling, Ansible‑driven deployment, platform architecture, and key features such as backup, inspection, user management, and SQL review.
Meituan’s DBA team progressed from simple scripting through tooling, productization, private‑cloud self‑service and full automation to an emerging intelligent‑operation model that leverages extensive data collection, risk‑driven pre‑warning, AI‑assisted analysis, and self‑healing mechanisms to meet rapid growth, stability and scalability demands.
In the era of big data, DBAs face higher demands and NoSQL technologies have risen, so this article shares GeTui's KV storage architecture evolution, operational challenges, NoSQL selection criteria, Codis+ enhancements, Aerospike evaluation, monitoring practices, and best‑practice recommendations for scalable database operations.
This article details a real‑world engineering case where a Percona XtraDB Cluster (PXC) was re‑architected to run separate OP and CLM MySQL instances on the same physical server, covering background, problem analysis, design choices, port configuration, directory restructuring, configuration files, step‑by‑step commands, automation script updates, and post‑change verification.
This article details Meituan Dianping's practical experience deploying MySQL Group Replication (MGR) for CMDB high availability, covering background, MGR fundamentals, configuration limits, parameter tuning, architecture design, deployment timeline, typical issues, a custom Python client, and daily operational practices.
This article details YY's journey in transforming its database operations—from early quality and efficiency challenges to a multi‑stage platform that automates resource pooling, high‑availability proxy, cost control, quality monitoring, and security, outlining future intelligent extensions.
This article shares practical experiences from a DBAplus Guangzhou tech salon, detailing three real Oracle database incident cases, the root‑cause analyses, and a three‑step framework for rapid resolution, prevention, and team management to maintain zero‑fault operations across thousands of database instances.
This guide shares a seasoned DBA's practical checklist covering environment awareness, hardware considerations, runtime monitoring, data security, routine operations, fault‑prevention plans, architecture insights, and the right mindset to help database professionals reduce errors and improve system stability.
This comprehensive guide shares a seasoned DBA's practical advice on environment awareness, hardware considerations, security, routine operations, architecture, and mindset to help database professionals avoid common pitfalls and improve reliability in MySQL production systems.
This comprehensive guide shares a senior DBA's hard‑learned lessons on MySQL environment setup, data security, routine operations, architecture insights, online execution tips, and the right mindset, helping database professionals prevent common pitfalls and improve reliability.
This guide shares a senior DBA’s hard‑learned lessons on mastering MySQL environments, ensuring data security, handling routine operations, designing robust architectures, and adopting the right mindset to reduce costly mistakes and improve reliability in production systems.
An in‑depth look at Blizzard’s Hearthstone outage reveals that a power interruption likely triggered storage failures in an Oracle RAC cluster, leading to corrupted blocks, incomplete recovery, and a reliance on backups, while highlighting broader lessons on database backup, disaster recovery, and operational decision‑making.
Zhou Tang, head of WeChat Pay operations at Tencent, shares how his team built a massive MySQL‑based payment platform handling up to 150 k transactions per second, covering background, DB‑CMDB design, change management, monitoring, security, high availability, and why Golang became their core development language.
This article explains how to standardize and automate MySQL management at scale, covering dedicated instance deployment, configuration consistency, multi‑instance creation, metadata collection, backup, monitoring, high‑availability with Zookeeper, and task orchestration using DBTask to achieve rapid, reliable database services.
This article explains how to standardize and automate MySQL operations—including multi‑instance deployment, metadata collection, monitoring, backup, and high‑availability using Zookeeper—so that large‑scale database services can be provisioned, managed, and scaled with minimal human intervention.
This article examines the operational challenges of oversized Redis instances—including slow failover, prolonged slave resynchronization, network‑induced avalanches, and persistence blocking—and offers practical mitigation strategies such as key expiration, data compression, and using high‑performance alternatives like Pika.
Qihoo 360 shares how it grew from a 2011 MongoDB adopter to running over 1500 instances handling 200 billion queries per day, detailing its architecture, key applications, migration decisions, backup strategies, scaling best practices, and lessons for future MongoDB projects.
This tutorial demonstrates how to create a MySQL database and table, import data from /etc/passwd, add an auto‑increment primary key, export selected records to a file, and perform common SQL queries, conditions, and table‑record manipulations such as insert, update, and delete.
This article explains why dropping large MySQL tables can heavily impact server I/O, compares ext3 and ext4 file‑system behavior, and provides a step‑by‑step method using hard links and the truncate tool to minimize downtime and I/O load.
This article presents a practical dual‑master MySQL high‑availability solution using keepalived and custom shell scripts that reliably detect master health, perform graceful VIP failover, and safely switch back after repairs, while ensuring data consistency and minimal downtime.
This article chronicles JD.com's transition from commercial to open‑source databases, detailing MySQL's rapid growth, the development of the JMySQL automation platform, and future directions for database design, security, monitoring, and performance optimization in large‑scale e‑commerce environments.
This guide provides step‑by‑step instructions for connecting to MySQL, creating and managing users and permissions, displaying, creating and deleting databases and tables, performing backups and restores, and executing various query operations such as selecting, updating, and aggregating data.
This article summarizes a detailed Q&A from the Efficient Operations talk, covering BlueKing’s integration with databases, agent resource management, alarm de‑duplication, automation workflows, development language choices, data handling, and the platform’s suitability for various enterprise environments.
During a lively Q&A session organized by the ‘Efficient Operations’ community, Oracle InnoDB principal developer Lai Zheng and Microsoft SQL Server product manager Lin Mo discuss SQL Server’s operational advantages over other databases, Microsoft’s product roadmap, common maintenance challenges, and the ideal career path for a modern DBA.
This article shares Meituan’s practical strategies for efficient database operations, covering rapid business growth handling, automated DDL workflows, systematic training, capacity planning, backup automation with xtrabackup, and real‑world Q&A on monitoring, replication, and disaster recovery.
