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This article explains how to locate and analyze MySQL slow queries, understand index structures and types, apply best practices for index creation, handle large pagination, manage transaction isolation and MVCC, and implement master‑slave replication and sharding strategies for high‑performance databases.
The case study details how an activity‑middleware platform tackled slow SQL problems by cleaning historic data, introducing sharding and Elasticsearch off‑loading, optimizing queries with proper indexes and simplified joins, and automating nightly deletions, ultimately cutting daily slow queries from thousands to double‑digit levels and boosting system stability.
This article examines MySQL slow‑query troubleshooting, explaining how the optimizer estimates costs, why indexes may be ineffective even when present, the impact of memory fragmentation, pitfalls of prefix indexes, index merging techniques, and additional resource‑related factors that can cause seemingly healthy SQL statements to become slow.
This article examines MySQL's cost estimation process, explains why added indexes may still be ineffective, discusses the impact of memory fragmentation, and presents practical techniques such as prefix index handling, index merging, and resource monitoring to improve slow‑query performance.
This article explains how slow MySQL queries degrade user experience, impact business operations, and consume resources, then details how to enable and interpret the slow query log, use EXPLAIN for query analysis, avoid common testing misconceptions, and apply four practical optimization strategies.
This technical report analyzes a high‑traffic MySQL deployment with three servers, detailing disk usage, table space, QPS and slow‑SQL issues, and presents a comprehensive governance plan that includes data migration, read‑traffic offloading to replicas, MyBatis interceptor implementation, JSF monitoring, and Python automation to reduce disk pressure and improve query performance.
This technical report describes the current high‑resource MySQL deployment, analyzes disk, table‑space, QPS and slow‑SQL issues, and presents a set of governance goals and concrete solutions—including data migration, query interception, and read‑from‑slave strategies—backed by code samples, tables and scripts to reduce load and improve stability before a major sales event.
This guide explains why slow queries occur in high‑traffic applications, outlines practical ways to monitor and fix them, and dives deep into using MySQL's EXPLAIN command to analyze index usage, interpret its output columns, and systematically improve query performance.
This article presents a detailed investigation of a MySQL master‑slave instance suffering from nightly SLA alerts due to slow‑query latency, analyzes the root causes with pt‑query‑digest and execution plans, proposes index redesign, demonstrates backup and restore with mydumper, compares online DDL and pt‑osc, and finally shows batch‑delete techniques to reduce load on large tables.
This article explains the new mysqld-long-query-time option added to MySQL 8.0.30's mysqldump tool, shows how to configure it, presents comparative experiments demonstrating its effect on slow‑query logs, and provides conclusions and additional notes for practical database backup scenarios.
This article examines a MySQL slow‑query incident caused by the optimizer using the primary clustered index instead of an appropriate secondary index, explains the underlying index structures, and presents solutions such as FORCE INDEX and migrating complex queries to Elasticsearch for long‑term performance improvement.
This article recounts a real‑world incident where MySQL 5.7 chose a sub‑optimal index, causing a three‑second slow query, and explains how the team identified the root cause, used EXPLAIN and optimizer trace, and applied fixes such as forced index hints and data cleanup.
This article presents a step‑by‑step investigation of a SELECT statement that became 1000× slower in OceanBase 3.2.3 BP8, explains why the optimizer chose an inefficient I5 index, describes the plan‑expiration logic, and provides reproducible scripts and practical recommendations for fixing the problem.
This article introduces a MyBatis‑based SQL analysis component that detects and prevents slow queries before they impact production by performing real‑time EXPLAIN analysis, offering optimization suggestions, and enabling dynamic SQL replacement, while detailing its design, configuration, performance testing, and practical advantages.
This article explains MySQL’s server and storage‑engine architecture, walks through the step‑by‑step execution of a SELECT statement, describes how indexes are organized, defines slow queries, shows how to detect and analyze them, and provides practical optimization examples and additional MySQL pitfalls.
This article details a real‑world incident of severe pagination slow queries, walks through the timeline of detection, diagnosis, and mitigation steps, and presents multiple MySQL optimization techniques—including ID‑based queries, sub‑queries, scroll queries, and join‑based solutions—to resolve deep pagination performance issues.
This article investigates why TRUNCATE and DROP TABLE statements appear in MySQL slow‑query logs, analyzes the internal execution paths and performance bottlenecks in MySQL 5.7 and 8.0, and proposes configuration‑based optimizations and debugging techniques to mitigate the latency.
This article explains how to collect extensive MySQL performance metrics—including connections, buffer pool statistics, lock information, SQL status, statement counts, throughput, server configuration, and slow‑query analysis—using only MySQL's native SHOW commands, providing practical commands, calculations, and optimization tips for effective database monitoring.
This article consolidates practical experience and author insights to guide OceanBase engineers in quickly diagnosing and resolving slow‑SQL performance issues by leveraging ODP and OBServer logs, key metrics, and systematic analysis steps.
This article explains why SQL queries become slow, how to capture slow queries using MySQL's slow query log, and provides detailed step‑by‑step methods for analyzing execution plans, profiling, optimizer tracing, and I/O parameters to identify and resolve performance bottlenecks.