Kaga Blog

What are the main MySQL storage engines and their differences? MySQL supports multiple storage engines, each with distinct characteristics: InnoDB: Default engine since MySQL 5.5 Supports ACID transactions Provides row-level locking Supports foreign keys and relationship constraints Uses clustered indexes MyISAM: Older engine, used as default before MySQL 5.5 Non-transactional Table-level locking Faster for read-heavy operations Supports full-text indexing Memory (HEAP): Stores data in RAM for fast access Non-persistent (data lost on restart) Useful for temporary tables and caches Archive: [Read More]

Input Tables INNER JOIN INNER JOIN returns only the rows where there’s a match between both tables based on the join condition. SELECT A.ID, A.Name, B.ID, B.Department FROM A INNER JOIN B ON A.ID = B.ID LEFT JOIN LEFT JOIN returns all rows from the left table (A), and the matched rows from the right table (B). If there’s no match, NULL values are used for the right table columns. [Read More]

What is Prometheus? Prometheus is an open-source systems monitoring and alerting toolkit. It collects and stores metrics as time series data, allowing for flexible querying and real-time alerting. What are the main components of Prometheus? The main components of Prometheus are: Prometheus server (for scraping and storing time series data) Client libraries (for instrumenting application code) Push gateway (for supporting short-lived jobs) Exporters (for services that don’t expose Prometheus metrics directly) Alertmanager (for handling alerts) How does Prometheus collect metrics? [Read More]

Protocol Buffers 1. Introduction Protocol Buffers (Protobuf) is a language-agnostic, platform-neutral extensible mechanism for serializing structured data. Developed by Google, it aims to be faster, smaller, and simpler than XML. This report provides an in-depth analysis of Protobuf’s principles, performance characteristics, and practical implications. 2. Historical Context and Development Origin: Developed internally at Google in the early 2000s. Open Source Release: Made publicly available in 2008. Versions: Proto1: Initial release (deprecated) Proto2: Introduced optional and required fields Proto3: Simplified syntax, removed required fields 3. [Read More]

A comprehensive guide to troubleshooting Redis performance issues 1. Introduction Redis is renowned for its high performance, capable of handling 100,000 operations per second. However, users may encounter unexpected latency issues in various scenarios: Same commands sometimes fast, sometimes slow Simple operations like SET and DEL taking unexpectedly long Temporary slowdowns that resolve themselves Sudden performance degradation after long periods of stability This comprehensive guide (approximately 20,000 words) aims to provide a thorough troubleshooting approach for Redis performance issues. [Read More]

1. 小作文 对所看到的数据、信息进行客观、准确、全面的描述。 1.1. 小作文图表分类 Line graph Bar chart Pie chart Table 1.2. 图表类小作文中的图表特征 静态图 时间点小于等于1 difference 动态图 时间点大于2 change 数据 最大值 最小值 等值 差值 倍数 大于 小于 趋势，动态图使用 上升 下降 波动 不变 程度大小 剧烈 平缓 1.3. 图表类小作文的段落组成 改写段 复述图表介绍 概述段 宏观概述 2～3句话 常见：2～3个要点 少数：1个要点 细节段 描述重要细节 4～5句话 细节段 描述重要细节 4～5句话 1.4. 图表类小作文改写段的写作 改写 描述性词汇同义替换 换位置 概括 1.5. 图表类小作文概述及细节内容的抓取 概述性：看型 看例子1 看例子2 细节性：对数 看例子1 1.6. 图表类小作文概述段的写作 Overview概述段的句子数量 折线图Overview概述段举例 概述段的引导词 Overall、In sum… [Read More]

【图表类小作文补充表达】 【表达：程度】 程度 逐渐的 slightly modestly gradually 稳定的 steadily sustained 显著的 noticeably remarkably markedly 巨大的 significantly remarkably dramatically rapidly sharply 大量的/少量的 a great/signifcant/major proportion (of…) (only) a fraction (of…) 最大量/少量 greatest/most significant proportion (of…) smallest/least significant proportion (of…) 以不同的程度 to different/varying degrees 【表达：分别的】 分别的 respectively each 【表达：年龄】 year old years old people of 18-24 years old year old 18-24 year old people aged people aged 18-24 year olds 18-24 year olds [Read More]

一、面向对象 程序设计 简介 对象之间的关系 依赖:对类 B 进行修改会影响到类 A 。 关联:对象 A 知道对象 B。类 A 依赖于类 B。 聚合:对象A知道对象B且由B构成。类A依赖于类B。 组合:对象 A 知道对象 B、由 B 构成而且管理着 B 的生命周 期。类 A 依赖于类 B。 实现: 类 A 定义的方法由接口 B 声明。 对象 A 可被视为对象 B。类 A 依赖于类 B。 继承: 类 A 继承类 B 的接口和实现， 但是可以对其进行扩 展。对象 A 可被视为对象 B。类 A 依赖于类 B。 二、设计模式简介 设计模式是针对软件设计中常见问题的工具箱， 其中的工具 就是各种经过实践验证的解决方案。 创建型模式提供创建对象的机制， 增加已有代码的灵活性和可复用性。 结构型模式介绍如何将对象和类组装成较大的结构， 并同时保持结构的灵活和高效。 行为模式负责对象间的高效沟通和职责委派。 三、软件设计原则 优秀设计的特征 代码复用 代码复用是减少开发成本时最常用的方式之一。 复用的三个层次： [Read More]

1. Your First Python Program 1.1. Diving In $ python3 humansize.py 1.2. Declaring Functions 1.2.1. Optional and Named Arguments def approximate_size(size, a_kilobyte_is_1024_bytes=True): 1.3. Writing Readable Code 1.3.1. Documentation Strings Triple quotes def approximate_size(size, a_kilobyte_is_1024_bytes=True): '''Convert a file size to human-readable form. Keyword arguments: size -- file size in bytes a_kilobyte_is_1024_bytes -- if True (default), use multiples of 1024 if False, use multiples of 1000 Returns: string ''' 1.4. The import Search Path >>> import sys >>> sys. [Read More]