This roundup covers Tencent Cloud's first domestic serverless PostgreSQL database, GitHub's free core features for all users, the nginx 1.17.10 release with a new auth_delay directive, a COBOL programmer's urgent call, and upcoming Linux dual‑boot on iPhone, among other tech headlines.
Meituan’s DBA team discovered that Intel Skylake CPUs dramatically increased PAUSE‑instruction latency, causing MySQL’s ut_delay spin‑wait loops to consume most CPU cycles and reduce write throughput, and they restored performance by back‑porting MySQL 8.0’s spin_wait_pause_multiplier patch to 5.7, upgrading to CentOS 7, and moving to Cascadelake hardware.
This tutorial explains how to configure Laravel's Eloquent ORM, create and customize model classes, manage table names, primary keys, timestamps, perform queries, insert, update, delete records, handle soft deletes, apply global and local scopes, and work with model events and observers, all with practical PHP code examples.
This article explains how to size and tune Druid's connection pool for high‑traffic Java applications, covering pool‑size formulas, timeout settings, keep‑alive behavior, essential XML properties, and version recommendations to prevent misleading SQL latency and improve overall database stability.
This tutorial demonstrates how to set up a Spring Cloud project, add MyBatis-Plus dependencies, configure the data source and MyBatis-Plus settings, and perform full CRUD operations with Java code examples, providing a practical guide for backend developers.
This guide explains how Laravel’s query builder offers a secure, fluent interface for constructing and executing database queries, covering result retrieval, filtering, aggregation, joins, unions, inserts, updates, deletes, and advanced features like raw expressions, JSON handling, and pessimistic locking.
This guide explains how to configure Laravel's supported databases, set up SQLite, implement read/write connection splitting, use multiple connections, execute raw SQL queries, listen to query events, and manage transactions—including deadlock handling and manual control—complete with code examples.
This guide explains how to use Laravel seeders to generate test data, covering creation of seeder classes via Artisan, inserting records manually or with model factories, calling additional seeders, and the commands needed to run or refresh database seeding.
Tencent Cloud is hosting a three‑month online technical salon, featuring dozens of senior database experts who will nightly dissect the architecture, implementation and best practices of domestic databases such as TDSQL, TBase and CynosDB/CDB, with April’s TBase sessions open for reservation via QR code and offering live‑stream giveaways.
This tutorial walks through creating the five microservice databases for the PassJava platform using PowerDesigner, detailing each service’s schema, showing screenshots, and providing the GitHub repository where the SQL files can be accessed.
This article shows backend developers how to use PyCharm Professional’s integrated Database tool and HTTP Client to connect to MySQL, perform visual CRUD operations, and test RESTful APIs directly within the IDE, eliminating the need for separate tools like Navicat and Postman.
This tutorial walks you through creating a web‑based employee management system that demonstrates MongoDB CRUD operations using Python, Flask, and Pipenv, covering project setup, environment configuration, code implementation for querying, adding, updating, and soft‑deleting records, and how to run the application.
This tutorial walks through pulling the Redis Docker image, creating configuration files, running the container, connecting with redis-cli, testing commands, enabling persistence, and installing a visual management tool, providing complete step‑by‑step instructions for Docker‑based Redis deployment.
This tutorial explains how to download the MySQL Docker image, create and run a MySQL container with volume mappings and environment variables, verify the container, connect to the database via Workbench, and access the container’s shell and host files.
This comprehensive guide introduces NoSQL concepts, classifies non‑relational databases, explains why MongoDB is suited for loosely structured data, walks through Windows and Linux installations, demonstrates using Robo 3T, and covers all CRUD operations, queries, updates, deletions, and data de‑duplication with practical code examples.
This tutorial explains how to install PyMongo, connect to local or remote MongoDB instances, choose databases and collections, and perform all common CRUD operations—including inserts, queries, updates, deletions, and special cases—using Python code examples and practical tips.
Senior DBA Yang Jianrong shares how standardized processes, robust security, and modern optimization—such as partitioning, middleware, and NoSQL—combined with high‑availability designs and self‑service tools like automated slow‑log analysis can streamline large‑scale MySQL operations, migrations, and continuous DBA learning.
The TVP Technical Closed‑door Conference gathered 44 experts across eight sessions to examine post‑pandemic technology trends—including blockchain as institutional infrastructure, cloud‑native databases and serverless computing, industrial internet transformation, data‑driven online education, federated learning for privacy‑preserving AI, and the shift toward resource‑focused technical entrepreneurship.
This article demonstrates how to build a reusable Python class with pyodbc to connect to Microsoft SQL Server, import CSV files, create tables, and perform common operations such as push, union, and drop, providing complete code examples and explanations for each step.
This article provides an in‑depth analysis of MySQL's filesort mechanism, explaining the original and modified algorithms, how sort and addon fields are calculated, memory allocation strategies, the role of temporary files, and practical tips to reduce excessive disk usage during sorting operations.
This article presents thirty actionable SQL performance recommendations—including selecting specific columns, using LIMIT, avoiding OR and functions in WHERE clauses, proper indexing, batch inserts, and query planning—each illustrated with clear examples and explanations to help developers write faster, more efficient queries.
This guide walks you through setting up a six-node Redis cluster using Docker Compose, configuring the necessary redis.conf settings, deploying the containers, initializing the cluster, and then integrating the cluster into a SpringBoot application via appropriate application.yml configurations and connection commands.
This article explains the purpose of Spring's @Transactional annotation, details its configurable attributes, and enumerates six typical scenarios—such as non‑public methods, wrong propagation settings, self‑invocation, and unsupported database engines—that cause the annotation to become ineffective, providing code examples and solutions.
This article examines various MySQL pagination methods—including simple LIMIT, offset impact, sub‑query, ID‑range, and temporary‑table strategies—provides detailed performance measurements on a table with over five million rows, and offers practical recommendations for speeding up large‑scale data retrieval.
This article presents ten practical Redis best‑practice guidelines—from avoiding the costly KEYS * command and leveraging SCAN, to using INFO for command statistics, employing hashes, setting expirations, selecting eviction policies, handling errors, scaling with clusters, understanding threading limits, and configuring Sentinel for high availability.
A detailed reference covering MySQL service management, connection commands, database and table operations, data types, indexes, joins, subqueries, transactions, backup, user privileges, and common SQL functions, complete with practical code examples.
This article explains several typical pitfalls that cause Spring's @Transactional annotation to be ineffective, such as unsupported database engines, unmanaged service beans, internal method calls, non‑public methods, default rollback rules, and missing transaction manager configuration, and provides practical solutions for each case.
This article explains the distinctions between UNION and UNION ALL, TRUNCATE and DELETE, TIMESTAMP and DATETIME, introduces composite and covering indexes, describes InnoDB versus MyISAM storage, the left‑most prefix rule, monotonic primary keys, int display length, SHOW INDEX fields, handling LIKE patterns, and efficient pagination techniques.
This article explains MySQL storage engines, compares MyISAM and InnoDB, introduces the main index types—B‑Tree, Hash, Full‑text, R‑Tree—details the structures and characteristics of B‑Tree, B‑Tree and B+Tree, and outlines key principles for creating effective indexes.
This article explains the seven common SQL JOIN variations—including INNER, LEFT, RIGHT, FULL OUTER, and their exclusive forms—illustrated with diagrams and complete SELECT statements, helping readers understand how each join type combines rows from two tables based on key relationships.
This article presents ten practical Redis best‑practice tips—including avoiding KEYS *, using SCAN, monitoring command stats, leveraging hashes, setting expirations, choosing eviction policies, handling errors, scaling with clusters, understanding threading, and configuring Sentinel—for improved performance, stability, and high availability.
This article explains core MySQL concepts, comparing UNION and UNION ALL, TRUNCATE versus DELETE, TIMESTAMP and DATETIME, composite and covering indexes, the left‑most prefix rule, clustered vs non‑clustered indexes, prefix indexes, InnoDB vs MyISAM storage, monotonic primary keys, column length display, SHOW INDEX fields, LIKE pattern pitfalls, and efficient pagination techniques.
This guide explains essential MySQL concepts such as the distinction between UNION and UNION ALL, TRUNCATE versus DELETE, TIMESTAMP versus DATETIME, the purpose and benefits of composite indexes, index storage engines, prefix indexes, covering indexes, the left‑most prefix rule, and efficient pagination techniques.
Idempotency ensures that repeated execution of an operation yields the same result as a single execution, and this article explains its importance in backend systems, outlines concepts, and presents practical techniques such as unique indexes, token mechanisms, pessimistic and optimistic locks, distributed locks, and API design for reliable, duplicate‑free processing.
This article presents ten practical Redis best‑practice recommendations—from avoiding the costly KEYS * command and using SCAN, to leveraging hashes, setting key expirations, choosing appropriate eviction policies, handling errors, scaling with clusters, and ensuring high availability—helping developers optimize performance and reliability.
This guide explains how to define Django model classes, map them to database tables, and use the makemigrations and migrate commands to generate and apply migrations, illustrated with Users and Files examples and the resulting SQL schema.
The article documents a puzzling MySQL 5.7.25 bug where RAND() in a derived table is unexpectedly re‑evaluated in the outer query, explains the step‑by‑step reproduction, analyses the cause, and provides official work‑arounds for both MySQL 5.7 and 8.0.
This article provides a comprehensive overview of MySQL InnoDB's internal architecture, covering its memory and disk structures, buffer pool, change buffer, adaptive hash index, log buffer, various tablespace types, page layout, undo and redo logs, double‑write buffer, transaction isolation levels, and how the engine satisfies ACID properties.
This tutorial explains how to integrate JDBC into a Spring Boot project, covering Maven dependencies, MySQL driver setup, application.yml datasource configuration, Spring Boot's auto‑configuration mechanism, JdbcTemplate usage, Swagger documentation, CRUD endpoint implementation, and solutions to typical connection errors.
This article provides a comprehensive guide to Python's file handling capabilities, covering built‑in functions, the csv module, numpy's load and save methods, pandas' extensive read/write utilities, Excel libraries such as xlrd and openpyxl, and popular database connectors like pymysql and sqlalchemy.
This guide walks through installing the EasyCode IntelliJ plugin, setting up a MySQL database, configuring a Spring Boot project, adding necessary Maven dependencies and application.yml settings, and using EasyCode to automatically generate CRUD code for the defined tables.
This guide explains MySQL fundamentals—including what a database is, transaction concepts and ACID properties, isolation levels and their effects, index structures and the left‑most prefix rule, storage engine differences, lock algorithms, and practical techniques for optimizing large tables such as partitioning and sharding.
This article walks through building a MySQL user table, defining the corresponding Java entity and MyBatis‑Plus mapper, and demonstrates basic query operations such as selectList, selectById, selectBatchIds, and selectByMap with full code examples and the generated SQL statements.
This tutorial demonstrates how to create a User table, define the corresponding entity and mapper classes, and perform basic MyBatis-Plus queries such as selectList, selectById, selectBatchIds, and selectByMap, including the required SQL scripts and Java code examples.
This tutorial walks you through installing the PyMySQL library, configuring connection parameters, establishing a Python‑MySQL link, and performing full CRUD operations—including creating tables, inserting, querying, updating, and deleting records—while also covering cursor methods and pandas integration.
This step‑by‑step guide explains how to add the PostgreSQL Yum repository, install PostgreSQL 12 client and server packages, initialize and start the database service, set the admin password, optionally enable remote access, and install the pgAdmin 4 web interface on CentOS 7 or 8 systems.
This article explains why a Redis instance creates 16 default databases, how they function as simple namespaces rather than separate applications, how to configure their number, and why Redis clusters support only a single database.
This whimsical yet technically detailed article explores how a mythic Hell‑DBMS could be architected, covering unique identifiers, massive concurrent writes, batch processing, NoSQL tree‑structured storage, disaster recovery, and a real‑world demo project that brings the underworld’s life‑and‑death ledger to life.
The article explains how to overcome performance degradation in DBLE‑based pagination by using a constant LIMIT clause, filtering with id‑based conditions, and adhering to sharding‑key constraints, while outlining practical steps, limitations, and best‑practice recommendations for continuous page navigation.
This article explains the concept of Hash Join in MySQL 8.0, compares it with Nested Loop joins, shows how to enable or force it with server variables or hints, and presents performance benchmarks that demonstrate its speed advantages on large datasets.
MySQL 8.0.19 introduces InnoDB ReplicaSet, Router enhancements, numerous SQL syntax additions, optimizer improvements, new Information Schema role views, security features, replication options, X Protocol compression, and a range of deprecations and bug fixes, providing a comprehensive update for database administrators and developers.
This article explains the principles of MySQL master‑slave replication and provides a detailed, step‑by‑step tutorial for configuring a master and a slave instance in a Docker environment, including configuration files, Docker commands, replication setup, testing, and troubleshooting.
This article demystifies MyBatis transaction handling by clarifying the true JDBC transaction methods, explaining Spring's propagation concepts, detailing the MyBatis Transaction and TransactionFactory interfaces, showcasing code examples, and exploring special cases such as auto‑commit nuances and connection‑pool interactions.
This article explains how MySQL X API (available since MySQL 5.7) can replace NoSQL databases by enabling the X protocol, showing configuration steps, equivalent insert examples, and detailed CRUD, indexing, and transaction operations with code snippets.
This guide explains the new Redis 6.0 cluster proxy feature, its purpose, and provides step‑by‑step instructions for installing, starting, and connecting to the proxy, including required GCC upgrades and example commands for a smooth setup.
Learn step-by-step how to query MySQL 5.7 and 8.0 to list the top three orders by amount for each month, using variables and ranking functions, with full SQL examples, explanations, and visual results.
This guide explains how Laravel handles session storage across HTTP requests, covering configuration files, built‑in drivers such as file, cookie, database, Memcached and Redis, custom driver creation, and common session operations like retrieving, storing, flashing, and regenerating IDs, with code examples throughout.
A chaotic incident‑response story shows how a DBA and SA scramble through VPN glitches, broken jump servers, log hunting, ad‑hoc config tweaks, unexpected bugs, security scans, and frantic firefighting to finally restore a production system, highlighting the messy reality of modern operations.
This guide walks you through setting up LDAP authentication for Zabbix, covering Active Directory OU creation, Zabbix server LDAP module verification, configuration parameters, user provisioning, fallback to internal authentication, and the related database tables and SQL commands.
The article explains why idempotent operations are essential in high‑traffic systems, defines idempotency, and presents a comprehensive set of techniques—including unique indexes, token validation, pessimistic and optimistic locking, distributed locks, select‑plus‑insert patterns, state‑machine design, and API safeguards—to guarantee consistent outcomes even under repeated requests.
This tutorial walks through creating an end‑to‑end Zhihu hot‑list project that scrapes the billboard page, stores the data with Flask‑SQLAlchemy, schedules periodic updates, exposes RESTful APIs, and finally displays the results in a uni‑app mini‑program with interactive charts.
This article explains ClickHouse's deployment architecture, read‑write separation, shard expansion steps, write‑batch strategies, a three‑layer monitoring model, and its practical application in Tencent's game analytics platform, offering concrete guidance for building a stable, high‑throughput analytics service.
In his CNBPS 2019 keynote, MongoDB architect Song Zhiqi discusses how the shift to cloud‑native architectures has amplified data volume and variety, outlines the key challenges such as rapid rollout, downtime, and unstructured data, and explains how MongoDB’s flexible, high‑availability document model addresses these issues while supporting modern micro‑service and Kubernetes ecosystems.
This article explains the fundamentals of LEFT JOIN in SQL, illustrates one‑to‑one, one‑to‑many, and many‑to‑many scenarios, compares ON versus WHERE conditions, and provides concrete MySQL and Hive examples with code snippets and visual diagrams to avoid common mistakes.
This article tackles the challenge of ordering hard‑coded role levels in a MySQL table by presenting ten distinct SQL solutions—including adding a helper column, using FIELD, FIND_IN_SET, CASE, subqueries, UNION, hash‑based formulas, and custom arithmetic—so that a "vice‑manager" (level 2) can be ranked above a "manager" (level 3).
In this interview, Ming Xiyuan, Technical Solutions Director at iKangSheng, shares practical guidance on selecting and deploying high‑availability MySQL solutions for the financial sector, covering planning pitfalls, hardware considerations, key configuration parameters, and the company’s product roadmap.
This article explains how to set Redis's maximum memory usage via configuration files or commands, describes the built‑in eviction strategies including noeviction, allkeys‑lru, volatile‑lru, allkeys‑random, volatile‑random, volatile‑ttl, and shows how to query and change these policies, while also covering LRU fundamentals, a Java LRU cache example, Redis's approximate LRU implementation, its 3.0 optimizations, and the newer LFU eviction algorithm.
The article explains why using the KEYS command on large Redis datasets can cause service blockage and demonstrates how the SCAN command with MATCH and COUNT options provides a non‑blocking, incremental way to list keys, including syntax and practical examples.
This article explains the importance of idempotent operations in backend systems, defines the concept, and presents practical techniques such as unique indexes, token mechanisms, pessimistic and optimistic locking, distributed locks, state‑machine design, and API patterns, complete with code snippets and diagrams.
This guide walks you through setting up the open‑source MySQL Monitor tool, covering environment preparation, installation, database schema import, host configuration, alert channel setup (email and WeChat), cron scheduling, and accessing the monitoring pages, all with a clean Chinese interface.
This article provides a comprehensive overview of Redis, explaining its core data structures, caching use cases, persistence mechanisms, high‑availability features like Sentinel and replication, clustering for horizontal scaling, and client‑side capabilities such as transactions, Lua scripting, pipelining, and distributed locks.
This comprehensive guide covers fundamental SQL Server operations such as creating databases, tables, indexes, and views, advanced techniques like set operators, subqueries, and linked servers, plus step‑by‑step instructions for replication, backup, compression, and automated synchronization using stored procedures and SQL Agent jobs.
This guide walks through installing Zabbix 4.4.0 on CentOS 7, configuring PostgreSQL, adding the TimescaleDB time‑series extension, setting up the Zabbix database, and tuning Linux, Nginx, and PHP so the monitoring platform runs smoothly with high‑performance time‑series storage.
This article explains how to use MySQL's EXPLAIN command, describes each column in its output—including id, select_type, table, type, possible_keys, key, key_len, ref, rows, filtered, and Extra—provides syntax examples, discusses join type rankings, and outlines the command's limitations for query performance analysis.
This weekly newsletter summarizes the latest DBLE, DTLE, and TXLE open‑source middleware updates, including bug fixes, new features, community Q&A, documentation releases, upcoming releases, and links to related videos and articles for developers.
This article explains how to quickly set up MySQL (as well as MariaDB and Percona) inside Docker containers, covering official images, running the latest version, connecting to the server, managing container lifecycle, passing server options, and handling multiple or specific MySQL versions.
This article examines common MySQL performance pitfalls such as inefficient LIMIT usage, implicit type conversion, suboptimal joins, mixed sorting, and unpushed predicates, and demonstrates eight practical rewriting techniques—including using max values, JOINs, WITH clauses, and early range reduction—to dramatically accelerate query execution.
This article introduces Xiaomi's open‑source SOAR tool, explains how to download and install the binary or source versions, walks through quick‑start commands, details key YAML configuration options and output formats, and describes four typical usage scenarios for SQL optimization and rewriting.
This article explains how Redis manages key expiration using EXPIRE, PEXPIRE, EXPIREAT, and PEXPIREAT commands, details the internal expires dictionary, demonstrates code examples for setting, retrieving, and removing TTL, and discusses the lazy and periodic deletion strategies along with their impact on persistence and replication.
This article explains how to design and implement a high‑frequency like/unlike feature for large social platforms using Spring Cloud, Redis caching, MySQL persistence, and Quartz scheduled jobs, covering Redis setup, data modeling, service interfaces, database schema, and periodic data synchronization.
The article explains the differences between cache and buffer, how Oracle’s log buffer and data buffer cache interact with various storage‑level caches, and why write‑back, battery‑backed caches, RAID and disk cache settings are crucial for maintaining data consistency during power loss.
This article explains MySQL date‑time data types, compares DATETIME and TIMESTAMP, shows how to map them to Java types, provides SQL examples, and demonstrates several methods for timezone conversion between MySQL and Java applications.
This article chronicles Alipay’s engineering journey from 2009 to the present, detailing how its distributed middleware, database sharding, load‑balancing, LDC, OceanBase, cloud‑native Service Mesh, big‑data and blockchain technologies have been continuously refined to support ever‑growing Double 11 transaction volumes.
This article explains how IO and CPU bottlenecks increase active database connections, describes horizontal and vertical sharding techniques, outlines practical steps and tools for implementing sharding, and discusses common challenges such as non‑partition key queries and expansion strategies.
This tutorial walks through setting up the Python happybase library, installing JPype for Java integration, and demonstrates end‑to‑end code examples for connecting to an HBase Thrift server, generating row keys via Java utilities, querying data, and handling type conversions.
The 2019 Data Technology Carnival in Beijing featured a presentation by iKesheng on how a private MySQL‑based RDS solution was designed, deployed, and operated in a state‑owned bank, covering node integration, operational standards, high‑availability scenarios, and multi‑site disaster recovery.
This guide introduces a set of scripts for installing MySQL 8.0, configuring master‑slave replication and group replication, detailing required files, command usage, repository location, and essential configuration notes for a three‑node deployment.
This guide explains how to create automated backup plans for MySQL and MariaDB databases on Jelastic PaaS, covering script configuration, cron scheduling, remote storage options, and restoring backups through phpMyAdmin, ensuring data safety and easy recovery.
This article explains the meaning of NULL in SQL, distinguishes the two conceptual types of unknown and not‑applicable, describes three‑valued logic, shows why IS NULL must be used instead of = NULL, and warns about pitfalls such as NOT IN with NULL and improper CASE expressions.
This article explains InfluxDB's Continuous Queries feature, covering configuration settings, basic and advanced syntax, execution timing, data range handling, result storage, and the use of RESAMPLE clauses with practical examples and code snippets.
This article explains why MySQL uses B+‑tree indexes by tracing the evolution from binary search trees through balanced trees and B‑trees, detailing the structure of clustered and non‑clustered indexes in InnoDB and illustrating how data is searched using these indexes.
This article demonstrates how to leverage uiautomator1.0 for Android automation by creating a shell‑based Context, accessing PackageManager, managing SQLite databases, monitoring app activities and processes, and implementing Chinese text input through AccessibilityNodeInfo.
This guide explains InfluxDB’s schemaless data types, best practices for designing tag‑and‑field schemas, and how to choose and configure its in‑memory or TSI indexes, including key parameters such as max‑series‑per‑database and max‑values‑per‑tag for optimal performance.
A detailed case study shows how a DELETE statement executed inside a MySQL stored procedure can switch binlog format to ROW, causing billions of bitmap operations on a partitioned table and resulting in severe master‑slave replication delay, and presents three practical solutions.
KeyDB is a high‑performance, multithreaded fork of Redis that retains full Redis compatibility while delivering up to twice the query throughput and 60 % lower latency, and the article explains its thread model, connection management, fastlock mechanism, and active‑replica features in detail.
This article introduces JDTX, a novel distributed transaction middleware that combines ACID guarantees, high performance, and 1PC architecture, explains its design principles, compares two‑phase commit with flexible transactions, details its MVCC and WAL implementation, and outlines integration with Apache ShardingSphere and future roadmap.
The article explains how MySQL 8.0 introduced the instant algorithm for adding columns, compares it with older copy and inplace‑rebuild methods, shows usage examples, performance test results, and outlines the restrictions and version differences of this fast DDL operation.
From a 2009 mandate to eliminate minicomputers to a 2019 TPC‑C world‑record, Alibaba’s decade‑long “de‑IOE” project forged OceanBase into a fully self‑developed, Oracle‑compatible database, delivering flexible architecture, talent growth, and massive cost savings while reshaping China’s IT landscape.
This article analyzes the MySQL slow query log in Percona 5.7, explaining how timestamps, execution time, lock time, and various log fields are derived from the source code, and clarifies the meaning of each output component for accurate performance debugging.
This article provides a comprehensive guide to Redis persistence mechanisms, covering the internal database structure, detailed operations of RDB snapshotting and AOF command logging, their configurations, advantages, drawbacks, hybrid persistence, and practical strategy recommendations for various deployment scenarios.
