1 views collected around this technical thread.
This guide explains what the MySQL slow query log is, why it matters for performance, how to check its status, enable it temporarily or permanently in Docker‑based deployments, troubleshoot command‑not‑found errors, read the log file, and filter entries to focus on the truly slow queries.
This article explains MySQL InnoDB's dual memory and on‑disk architecture, detailing the various tablespace types (system, file‑per‑table, general, undo, temporary), their internal structures (segments, extents, pages), configuration tips, and how tables, row formats, primary keys, auto‑increment lock modes, and B+Tree indexes are organized and managed.
An experienced DBA explains why adding a new column in MySQL can unexpectedly raise duplicate entry errors during online DDL, detailing the role of primary and unique keys, the innodb_online_alter_log_max_size setting, and how concurrent DML operations cause the conflict.
Learn step‑by‑step how to troubleshoot MySQL master‑slave replication problems, from verifying component roles and executing the correct SHOW SLAVE STATUS command inside the MySQL client, to fixing missing command errors, checking IO/SQL threads, and restarting replication in Docker‑based environments.
This article explains MySQL's four transaction isolation levels—READ UNCOMMITTED, READ COMMITTED, REPEATABLE READ, and SERIALIZABLE—through step‑by‑step examples, demonstrating their effects on dirty reads, non‑repeatable reads, phantom reads, and performance considerations, helping developers choose the appropriate level.
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.
This article explains MySQL's storage architecture, compares the DELETE, TRUNCATE, and DROP commands, shows their performance and side‑effects, and provides practical guidance on choosing the safest and most efficient way to remove data from a MySQL table.
This article explains why excessive MySQL joins can cause performance problems and provides a comprehensive set of techniques—including query splitting, temporary tables, denormalization, index tuning, query rewriting, result‑set reduction, configuration tweaks, big‑data tools, and summary tables—to effectively optimize multi‑table join queries.
This article explains MySQL’s locking mechanisms, categorizing locks by performance, operation type, data granularity, and finer‑grained levels such as gap and next‑key locks, and offers guidance on selecting the appropriate lock strategy for reliable concurrent database operations.
This article explains how MySQL's InnoDB engine implements full‑text search using inverted indexes, shows how to create and use full‑text indexes with various query modes, demonstrates Boolean operators and query expansion, and covers index removal techniques.
This article explains the MySQL Connection Control Plugins introduced in 5.7.17, how improper configuration can lead to connection backlog and database hangs, and provides step‑by‑step installation, parameter tuning, testing procedures, and mitigation strategies to resolve the issue.
Learn how to quickly pinpoint MySQL performance bottlenecks on AlmaLinux by using built‑in tools like top, iotop, ss, and netstat, and automate snapshot collection with a simple Bash script that records system and container metrics for later analysis.
This article presents a comprehensive guide on applying Linux Cgroups to isolate MySQL resources, covering CPU, memory, I/O, and network bandwidth controls, detailed configuration steps, performance testing with sysbench, and practical observations to ensure stable and predictable database behavior.
This article provides a step‑by‑step tutorial for DBAs to design a reliable MySQL backup strategy, write a Bash automation script, schedule it with cron, and perform restoration drills using Docker containers, while covering directory planning, command checks, cleanup, and common troubleshooting.
This article presents a series of MySQL interview questions and answers that illustrate typical situations where indexes become ineffective—such as leading wildcards in LIKE, NOT IN, NOT EXISTS, functions, inequality operators, OR conditions, mismatched ORDER BY, large result sets, and explains how to analyze execution plans and use FORCE INDEX to improve performance.
The article details a MySQL 5.7 bug where rollback SQL generated for a JSON NOT NULL column produces an empty string instead of NULL, explains the underlying binlog behavior, reproduces the issue with sample tables, and provides a practical workaround by converting the JSON column to TEXT before re‑importing the data, while recommending strict SQL_MODE for production.
The article explains how to retrieve coupon templates linked to a specific product ID in MySQL, compares a simple LIKE‑based fuzzy search with a more accurate multi‑value JSON index approach, and provides step‑by‑step SQL code and performance considerations.
This article introduces an open‑source novel content management system featuring a front‑end portal, writer and platform back‑ends, and a crawler module, detailing its functional modules, Springboot‑based architecture, installation steps, database setup, crawling methods, and access URLs.
This article explains MySQL InnoDB locking mechanisms—including row, record, gap, next‑key, and intention locks—illustrates each type with SQL statements and performance_schema data, and shows how they interact during concurrent transactions.
To avoid lock, page split, and index degradation when adding fields to billion‑row core tables, this article presents a practical solution that uses dynamic field extension via configurable management, JSON‑based extension fields, and an extension‑table architecture integrated with Elasticsearch for storage and retrieval.