A public account focused on workplace, career growth, team management, and self-improvement. The author is the writer of books including 'SpringBoot Technology Insider' and 'Drools 8 Rule Engine: Core Technology and Practice'.
Understanding MySQL's clustered indexes—including their definition, selection rules, customization via primary key design, practical creation examples, and key design considerations—helps developers optimize query performance and storage efficiency in InnoDB tables for various workloads.
This article provides a comprehensive review of MySQL’s two primary index types—clustered (clustered index) and non‑clustered (non‑clustered index)—explaining their storage mechanisms, performance trade‑offs, typical use cases, and best‑practice guidelines for selecting the appropriate index in database design.
Learn how to leverage MySQL's EXPLAIN and EXPLAIN ANALYZE commands to diagnose query performance, understand each column of the output, choose appropriate indexes, and apply practical optimization steps—including multi‑column indexes—to dramatically reduce row scans and speed up queries.
This article explains how indexes boost query speed but also incur storage, write‑performance, and maintenance costs, offering practical SQL scripts and guidelines for auditing, testing, and safely removing unnecessary indexes.
This article explains the N+1 query performance issue, demonstrates a naïve Python/SQLite implementation that triggers N+1 queries, compares its runtime, and then shows how using SQL JOINs, GROUP BY, and nested data structures can dramatically improve query efficiency and reduce latency.
This guide walks through MySQL's join operations—inner, left, right, and full outer—using a simple grocery‑items schema, showing how to create tables, write correct queries, avoid common pitfalls like unintended cross joins, apply aliases, and filter unassociated rows with WHERE and UNION.
This guide explains why MySQL cannot index JSON columns directly and demonstrates two practical work‑arounds—using generated columns in MySQL 5.7 and functional indexes in MySQL 8.0.13—to efficiently index a nested request.email field for fast queries.
Drawing on interviews with hundreds of technical candidates, this article outlines practical resume‑screening criteria, the three key interview dimensions—problem‑solving, fundamentals, and soft skills—and compares the strengths of Go developers from Java, PHP, and native Go backgrounds.
This article explains the performance differences among MySQL's COUNT(*), COUNT(1), and COUNT(column) forms, showing that COUNT(*) and COUNT(1) are equivalent and generally faster than counting specific columns, and provides practical recommendations for accurate row counting.
This article explains the fundamental differences between MySQL VARCHAR and CHAR types, covering their definitions, length limits, storage overhead, character‑set effects, practical examples, and guidelines for choosing the appropriate column type in database design.
