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2820 articles · Page 9 of 29
ITPUB
ITPUB
Jan 8, 2024 · Databases

How I Cut an 8‑Second SQL Query to 0.7 Seconds: Step‑by‑Step Optimization

This article walks through a real‑world case of a slow MySQL query that took 8 seconds, explains how the original use of EXISTS and NOT EXISTS caused performance bottlenecks, and details two successive rewrites—first using JOIN + GROUP BY, then replacing NOT EXISTS with NOT IN—bringing execution time down to 0.7 seconds while highlighting key indexing and testing lessons.

IndexesMySQLPerformance Tuning
0 likes · 7 min read
How I Cut an 8‑Second SQL Query to 0.7 Seconds: Step‑by‑Step Optimization
Aikesheng Open Source Community
Aikesheng Open Source Community
Jan 8, 2024 · Databases

AIKOS Open Source Community Weekly Newsletter – SQLE Release, Community Updates, and Selected Database Articles

This newsletter announces the SQLE 3.2401.0-pre1 release with automatic data masking, shares recent community development work, outlines upcoming plans, and curates several technical articles covering MySQL EXPLAIN enhancements, transaction fundamentals, hardware considerations for database stability, consistent backup techniques, and efficient JDBC connection testing.

CommunityData MaskingMySQL
0 likes · 6 min read
AIKOS Open Source Community Weekly Newsletter – SQLE Release, Community Updates, and Selected Database Articles
Java High-Performance Architecture
Java High-Performance Architecture
Jan 5, 2024 · Databases

Why Manticore Search Could Replace Elasticsearch: 10× Faster, Open‑Source DB

Discover how Manticore Search, an open‑source C++‑based high‑performance search engine, claims to outperform Elasticsearch by up to 15‑times, offering cost‑effective, multi‑threaded full‑text search, SQL compatibility, Docker deployment, and extensive language client support for diverse data workloads.

C++DockerElasticsearch alternative
0 likes · 6 min read
Why Manticore Search Could Replace Elasticsearch: 10× Faster, Open‑Source DB
MaGe Linux Operations
MaGe Linux Operations
Jan 4, 2024 · Databases

Master MySQL Stored Procedures: Concepts, Syntax, and Real-World Examples

This guide explains MySQL stored procedures, covering their definition, benefits, parameter types, creation syntax, delimiter handling, multiple practical examples, calling conventions, debugging tips, and hands‑on exercises, enabling developers to efficiently write, test, and manage reusable SQL routines.

Code examplesMySQLSQL
0 likes · 17 min read
Master MySQL Stored Procedures: Concepts, Syntax, and Real-World Examples
Weimob Technology Center
Weimob Technology Center
Jan 2, 2024 · Big Data

How to Efficiently Test BI Reports in a Hive‑StarRocks Data Warehouse

This article details practical methods for testing BI reports built on Hive and StarRocks, covering the report creation workflow, testing characteristics, SQL writing techniques, impact analysis, data warehouse simplification, and the application of data quality tools to ensure accurate and efficient reporting.

BI testingData QualityData Warehouse
0 likes · 9 min read
How to Efficiently Test BI Reports in a Hive‑StarRocks Data Warehouse
Selected Java Interview Questions
Selected Java Interview Questions
Dec 27, 2023 · Databases

Fast Database Migration Methods: Logical, File, and Physical Approaches with MySQL

This article explains three MySQL data‑migration techniques—logical migration using mysqldump, file‑based migration with SELECT … INTO OUTFILE and LOAD DATA INFILE, and physical migration by copying InnoDB files—detailing commands, performance considerations, and practical steps for each method.

File MigrationLogical MigrationPhysical Migration
0 likes · 12 min read
Fast Database Migration Methods: Logical, File, and Physical Approaches with MySQL
DataFunTalk
DataFunTalk
Dec 27, 2023 · Big Data

Apache Flink 2023: Core Technical Achievements and Future Directions

The article reviews Apache Flink's rapid development over the past decade, highlighting its 2023 community growth, SIGMOD award, major releases, streaming SQL enhancements, incremental checkpointing, batch maturity, cloud‑native scaling, and integration with the emerging Lakehouse architecture.

Apache FlinkBig DataCheckpoint
0 likes · 11 min read
Apache Flink 2023: Core Technical Achievements and Future Directions
ITPUB
ITPUB
Dec 25, 2023 · Big Data

Unlock Complex Data Scenarios with Simple MaxCompute SQL Techniques

This article shows how flexible, divergent thinking combined with basic MaxCompute (ODPS) SQL syntax can solve complex data problems such as generating sequences, splitting intervals, performing permutations and combinations, and analyzing continuous activity, providing step‑by‑step examples, SQL code snippets, and practical results.

IntervalsMaxComputeSQL
0 likes · 24 min read
Unlock Complex Data Scenarios with Simple MaxCompute SQL Techniques
Full-Stack Internet Architecture
Full-Stack Internet Architecture
Dec 22, 2023 · Databases

Understanding NULL Values in MySQL

This article explains the nature of NULL in MySQL, demonstrates why comparisons with = or != fail, shows the correct IS NULL/IS NOT NULL syntax, and discusses how NULL behaves with DISTINCT, GROUP BY, ORDER BY, and aggregate functions.

AggregationMySQLNULL
0 likes · 6 min read
Understanding NULL Values in MySQL
Programmer DD
Programmer DD
Dec 22, 2023 · Backend Development

Master Spring Boot 3.2 JdbcClient: Fluent API for Simple DB Operations

This guide introduces Spring Boot 3.2's new JdbcClient, explains how to add the dependency, inject it, and perform fluent, chainable CRUD operations—including queries by ID, custom conditions, named parameters, map parameters, row mapping, and inserts—while highlighting its advantages over traditional ORM tools.

Fluent APIJavaJdbcClient
0 likes · 7 min read
Master Spring Boot 3.2 JdbcClient: Fluent API for Simple DB Operations
Aikesheng Open Source Community
Aikesheng Open Source Community
Dec 20, 2023 · Databases

Analyzing and Resolving Slow Query Plan Issues in OceanBase 3.2.3

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.

OceanBasePerformance TuningPlan Cache
0 likes · 19 min read
Analyzing and Resolving Slow Query Plan Issues in OceanBase 3.2.3
Aikesheng Open Source Community
Aikesheng Open Source Community
Dec 14, 2023 · Databases

SQLE 3.0 Installation Guide: RPM and Docker Deployment

This article provides a step‑by‑step guide for installing the open‑source SQLE 3.0 SQL quality management platform using both RPM packages and Docker containers, covering environment preparation, configuration file adjustments, service startup, common issues, and troubleshooting tips.

DockerInstallationRPM
0 likes · 11 min read
SQLE 3.0 Installation Guide: RPM and Docker Deployment
Data Thinking Notes
Data Thinking Notes
Dec 12, 2023 · Artificial Intelligence

Boosting Text‑to‑SQL Accuracy with Prompt Engineering and LLMs

This article examines the challenges of LLM‑based Text‑to‑SQL such as hallucinations, data‑security risks, and user input errors, and presents prompt‑engineering strategies, fine‑tuning comparisons, prompt types, code examples, and experimental results to improve reliability and cost‑effectiveness.

Artificial IntelligenceLLMLangChain
0 likes · 15 min read
Boosting Text‑to‑SQL Accuracy with Prompt Engineering and LLMs
StarRocks
StarRocks
Dec 12, 2023 · Databases

How StarRocks Enables Real-Time Updates in Analytical Databases

The article explains why analytical databases struggle with real‑time data changes due to columnar storage, complex indexes and distributed processing, and then details StarRocks' primary‑key model, adaptive update mode, bitmap indexes, row/column partial updates, and practical SQL upsert techniques to achieve low‑latency updates without sacrificing query performance.

Partial UpdatePrimary KeyReal-Time Update
0 likes · 15 min read
How StarRocks Enables Real-Time Updates in Analytical Databases
Architect
Architect
Dec 11, 2023 · Backend Development

How to Integrate Dataway into a Spring Boot Project – A Step‑by‑Step Guide

This article walks through the complete process of adding Dataway to a Spring Boot application, covering Maven dependencies, configuration properties, database schema creation, data source setup, Hasor module integration, enabling Hasor in Spring, and finally creating and testing API endpoints using both SQL and DataQL, all illustrated with concrete code snippets and log output.

API ConfigurationDataQLDataway
0 likes · 16 min read
How to Integrate Dataway into a Spring Boot Project – A Step‑by‑Step Guide
Python Programming Learning Circle
Python Programming Learning Circle
Dec 7, 2023 · Fundamentals

Practical Python Implementation of Credit Card User Profiling Using SQL and Data Visualization

This tutorial demonstrates a complete workflow for building credit‑card user profiles by first extracting and transforming the KDD99 dataset with SQL, then applying Python libraries such as pandas, matplotlib, and seaborn to perform descriptive statistics and produce visualizations of demographic, transaction, and financial characteristics.

PythonSQLSeaborn
0 likes · 12 min read
Practical Python Implementation of Credit Card User Profiling Using SQL and Data Visualization
Efficient Ops
Efficient Ops
Dec 6, 2023 · Databases

When and How to Use MySQL Locks: A Deep Dive into Explicit and Implicit Locking

This article explains MySQL's explicit and implicit locking mechanisms, illustrates how transaction isolation levels affect lock scope, provides practical SQL examples for various scenarios, and offers guidelines on when to apply pessimistic locks versus optimistic approaches to maintain database performance.

LockingMySQLSQL
0 likes · 13 min read
When and How to Use MySQL Locks: A Deep Dive into Explicit and Implicit Locking
Architecture Digest
Architecture Digest
Dec 6, 2023 · Databases

MySQL Query Optimization and Index Tuning: From Subqueries to Joins

This article analyzes a slow MySQL query that scans millions of rows to find students scoring 100 in Chinese, then demonstrates how adding appropriate single‑column and composite indexes, rewriting the query as a join, and using covering indexes can reduce execution time from hours to milliseconds.

MySQLPerformance TuningQuery Optimization
0 likes · 10 min read
MySQL Query Optimization and Index Tuning: From Subqueries to Joins
Programmer DD
Programmer DD
Dec 5, 2023 · Databases

Master the Basics of SQL: Understanding Tables, Keys, and Queries

This article introduces SQL as the standard language for relational databases, explains how data is organized into tables with primary and foreign keys, and walks through essential keywords like SELECT, WHERE, and JOIN to query and relate data effectively.

Foreign KeyJOINPrimary Key
0 likes · 5 min read
Master the Basics of SQL: Understanding Tables, Keys, and Queries
Sanyou's Java Diary
Sanyou's Java Diary
Dec 4, 2023 · Backend Development

When Pagination Breaks: Real‑World Bugs and Practical Fixes

This article recounts three production‑level pagination bugs encountered in a payment system, explains why they occurred—ranging from naive batch processing to MySQL's nondeterministic LIMIT behavior—and shows how proper pagination, ThreadLocal cleanup, and deterministic ordering resolve the issues.

MySQLSQLbackend
0 likes · 16 min read
When Pagination Breaks: Real‑World Bugs and Practical Fixes
DataFunTalk
DataFunTalk
Dec 3, 2023 · Big Data

NetEase Data: Practices and Architecture of a Metrics Middle Platform

This article presents NetEase Data's end‑to‑end experience in building a metrics middle platform, covering product evolution, the motivations for a unified metrics layer, core technologies such as a logical semantic model, a custom metric query language, engine‑agnostic execution, and future roadmap plans.

Data AnalyticsDataOpsMetrics Platform
0 likes · 12 min read
NetEase Data: Practices and Architecture of a Metrics Middle Platform
php Courses
php Courses
Dec 2, 2023 · Databases

Index Optimization Techniques for PHP and MySQL Multi‑Table Queries

Effective index design, including single‑table, foreign‑key, composite, and covering indexes, along with optimizer hints, can dramatically improve the performance of multi‑table queries in PHP‑MySQL applications, and the article provides practical examples and SQL statements for each technique.

Database PerformanceIndex OptimizationMySQL
0 likes · 4 min read
Index Optimization Techniques for PHP and MySQL Multi‑Table Queries
Java Architect Essentials
Java Architect Essentials
Nov 29, 2023 · Backend Development

Performance Tuning of a Java Backend Service: From 50/s to 500/s Through Profiling, Thread‑Pool, and SQL Optimization

The article details a step‑by‑step investigation and optimization of a Java backend service that initially delivered only 50 requests per second under load, covering profiling, slow‑SQL fixes, thread‑pool tuning, JVM memory adjustments, and Spring bean creation overhead to approach the target 500 req/s.

JavaPerformanceProfiling
0 likes · 14 min read
Performance Tuning of a Java Backend Service: From 50/s to 500/s Through Profiling, Thread‑Pool, and SQL Optimization
Top Architect
Top Architect
Nov 28, 2023 · Databases

Performance Comparison of JOIN vs IN in MySQL Queries

This article experimentally compares the performance of JOIN and IN approaches for retrieving order and user data in MySQL, showing that JOIN is faster on small datasets while IN may become costly with large data volumes, and discusses code implementations and practical conclusions.

INJOINMySQL
0 likes · 10 min read
Performance Comparison of JOIN vs IN in MySQL Queries
Architect
Architect
Nov 27, 2023 · Backend Development

Why 500 req/s Became 50 req/s: A Deep Dive into Spring Bean Creation Bottlenecks

A ToB system that seemed able to handle 500 requests per second stalled at 50 req/s due to hidden lock contention in prototype‑scoped Spring beans, slow SQL updates, excessive logging, and thread‑pool misconfiguration, prompting a step‑by‑step performance investigation and multiple optimizations.

JavaOptimizationPerformance
0 likes · 16 min read
Why 500 req/s Became 50 req/s: A Deep Dive into Spring Bean Creation Bottlenecks
ITPUB
ITPUB
Nov 25, 2023 · Databases

8 Common SQL Pitfalls and How to Optimize Them for Faster Queries

This article examines eight frequent MySQL performance problems—including misuse of LIMIT, implicit type conversion, sub‑query updates, mixed ordering, EXISTS, condition push‑down, early limiting, and intermediate result push‑down—and provides concrete rewrite techniques and example code that dramatically reduce execution time.

IndexesLimitsMySQL
0 likes · 13 min read
8 Common SQL Pitfalls and How to Optimize Them for Faster Queries
Python Programming Learning Circle
Python Programming Learning Circle
Nov 22, 2023 · Big Data

E‑commerce User Behavior Analysis and KPI Modeling with Python and SQL

This study analyzes JD e‑commerce operational data from February to April 2018, employing Python and SQL to compute key metrics such as PV, UV, conversion rates, attrition, purchase frequency, time‑based behavior, funnel analysis, retention, product sales, and RFM segmentation, and provides actionable recommendations for improving user engagement and sales performance.

RFMSQLdata analysis
0 likes · 30 min read
E‑commerce User Behavior Analysis and KPI Modeling with Python and SQL
MaGe Linux Operations
MaGe Linux Operations
Nov 21, 2023 · Databases

Boost MySQL Performance: 10 Proven Optimization Techniques

This guide presents ten practical MySQL performance optimization methods—including index creation, query rewriting, limiting result sets, avoiding SELECT *, reducing joins, using proper data types, caching with Redis, and server configuration tweaks—each illustrated with concrete SQL code examples to help you speed up your database operations.

Database TuningMySQLSQL
0 likes · 11 min read
Boost MySQL Performance: 10 Proven Optimization Techniques
Architect
Architect
Nov 18, 2023 · Databases

JOIN vs IN: Choosing the Faster MySQL Query Method

Through a series of local experiments on MySQL tables with varying data volumes, this article analyzes the performance trade‑offs between JOIN queries and IN‑list queries, detailing execution plans, PHP benchmarking, and the impact of large IN lists on query speed and reliability.

INJOINMySQL
0 likes · 10 min read
JOIN vs IN: Choosing the Faster MySQL Query Method
Architect's Guide
Architect's Guide
Nov 18, 2023 · Backend Development

Preventing Coupon Over‑Issuance in High‑Concurrency Scenarios with Java, SQL, and Redis Distributed Locks

This article analyzes a coupon‑claiming race condition that caused stock to become negative under load and presents four solutions—including Java synchronized blocks, SQL conditional updates, Redis SETNX locks, and Redisson client locks—to reliably prevent over‑issuance in backend systems.

CouponDistributed LockJava
0 likes · 12 min read
Preventing Coupon Over‑Issuance in High‑Concurrency Scenarios with Java, SQL, and Redis Distributed Locks
21CTO
21CTO
Nov 12, 2023 · Databases

From INGRES to PostgreSQL: How the Open‑Source RDBMS Became a Developer Favorite

This article traces PostgreSQL's origins from the 1980s INGRES project, compares navigation and relational databases, outlines its evolution through Postgres95 to PostgreSQL, and highlights ten modern features that make it a powerful, scalable, and secure choice for developers today.

Data TypesDatabase FeaturesPostgreSQL
0 likes · 17 min read
From INGRES to PostgreSQL: How the Open‑Source RDBMS Became a Developer Favorite
JD Tech
JD Tech
Nov 9, 2023 · Databases

Optimizing Pagination Queries for Billion‑Row MySQL Tables

This article analyzes the performance problems of LIMIT‑based pagination on massive MySQL tables and presents three progressively more efficient solutions—including a simple LIMIT approach, a tag‑record method using the last primary key, and a range‑limit method with cached min‑ID—along with best‑practice indexing recommendations to keep query latency in the tens of milliseconds even for tables containing billions of rows.

Index OptimizationLarge DataMySQL
0 likes · 12 min read
Optimizing Pagination Queries for Billion‑Row MySQL Tables
Laravel Tech Community
Laravel Tech Community
Nov 7, 2023 · Databases

SQLite 3.44.0 Release Highlights and New Features

SQLite 3.44.0 introduces enhanced aggregate functions with ORDER BY support, new scalar functions like concat(), string_agg(), expanded strftime() format specifiers, additional C APIs, stricter PRAGMA behavior, improved query planner optimizations, runtime detection of long‑double support, and default UTF‑8 handling in the Windows CLI.

Database EngineSQLSQLite
0 likes · 5 min read
SQLite 3.44.0 Release Highlights and New Features
DataFunTalk
DataFunTalk
Nov 7, 2023 · Big Data

Comprehensive Guide to User Crowd Analysis: Distribution, Metrics, Drill‑down, Cross, and Comparative Methods with Implementation Details

This article explains the concepts, analytical methods, visualizations, and SQL implementation of user crowd analysis—including distribution, metric, drill‑down, cross, and comparative analyses—while also covering trend monitoring, TGI calculation, and handling of array‑type tags in ClickHouse and Hive.

ClickHouseData VisualizationSQL
0 likes · 17 min read
Comprehensive Guide to User Crowd Analysis: Distribution, Metrics, Drill‑down, Cross, and Comparative Methods with Implementation Details
Tencent Cloud Developer
Tencent Cloud Developer
Nov 6, 2023 · Databases

MySQL Lock Mechanisms: When, How, and When Not to Use

The article explains MySQL’s explicit and implicit lock mechanisms—including SELECT … FOR UPDATE, metadata, row, gap, and next‑key locks—how isolation levels affect them, and offers practical guidelines such as using optimistic locking, indexing locked columns, and avoiding long transactions to prevent phantom reads, deadlocks, and performance issues.

Database PerformanceInnoDBLocking
0 likes · 15 min read
MySQL Lock Mechanisms: When, How, and When Not to Use
dbaplus Community
dbaplus Community
Nov 5, 2023 · Backend Development

Three Hidden Pagination Pitfalls That Can Break Your Production System

The article recounts three real‑world pagination bugs—batch‑processing loops, misuse of MyBatis PageHelper, and nondeterministic results from identical ORDER BY values—explaining why they occur, how they manifest in production, and concrete fixes to avoid data loss or endless loops.

MyBatisMySQLSQL
0 likes · 15 min read
Three Hidden Pagination Pitfalls That Can Break Your Production System
ITPUB
ITPUB
Nov 2, 2023 · Databases

How to Diagnose and Fix Slow SQL Queries: Practical Steps and Real Examples

This article explains why slow SQL queries become a major risk for service stability, outlines a step‑by‑step investigation process using EXPLAIN, and presents multiple real‑world case studies with code snippets and optimization principles to quickly locate and resolve performance bottlenecks.

EXPLAINMySQLSQL
0 likes · 14 min read
How to Diagnose and Fix Slow SQL Queries: Practical Steps and Real Examples
Laravel Tech Community
Laravel Tech Community
Nov 1, 2023 · Databases

MySQL my.cnf Configuration Parameters Reference

This article presents a detailed reference of MySQL server configuration options (my.cnf), explaining each setting such as storage engine, networking, replication, logging, cache sizes, and performance‑related parameters to help administrators fine‑tune their databases.

Database ConfigurationMySQLPerformance Tuning
0 likes · 12 min read
MySQL my.cnf Configuration Parameters Reference
dbaplus Community
dbaplus Community
Nov 1, 2023 · Databases

What’s New in MySQL 8.2.0? Features, Deprecations, and Firewall Updates

MySQL 8.2.0, released on October 25, 2023, introduces audit‑log cleanup scripts, FIDO‑based authentication, named‑parameter support, numerous deprecations, firewall reload scheduling, expanded SQL syntax options, and new client and server features while dropping outdated functions and variables.

Database FeaturesMySQLSQL
0 likes · 9 min read
What’s New in MySQL 8.2.0? Features, Deprecations, and Firewall Updates
ITPUB
ITPUB
Nov 1, 2023 · Databases

Doris 2.0.2 vs 1.2.3: Real‑World Query Performance Comparison

After upgrading a Doris cluster from version 1.2.3 to 2.0.2, the author runs a series of SQL benchmarks—including PK lookups, top‑client queries, distinct counts on low‑ and high‑cardinality columns, minute‑level session analysis, and full‑table deduplication—to measure execution times, revealing mixed performance gains and regressions across the seven test scenarios.

Database UpgradeDorisPerformance Benchmark
0 likes · 9 min read
Doris 2.0.2 vs 1.2.3: Real‑World Query Performance Comparison
Selected Java Interview Questions
Selected Java Interview Questions
Oct 30, 2023 · Databases

Understanding SELECT ... FOR UPDATE Locks in MySQL

This article explains how MySQL's SELECT ... FOR UPDATE statement applies different lock types—row, table, or none—depending on whether the WHERE clause uses primary keys, unique indexes, regular indexes, range queries, non‑indexed fields, or returns no rows, illustrated with practical transaction examples.

SELECT FOR UPDATESQLTransaction
0 likes · 9 min read
Understanding SELECT ... FOR UPDATE Locks in MySQL
Aikesheng Open Source Community
Aikesheng Open Source Community
Oct 30, 2023 · Databases

ActionTech Open Source Community Weekly Newsletter – SQLE Updates, Technical Articles, and Events

The newsletter announces the SQLE 3.0 release with new UI and demo environments, highlights the SQLE 2.2310.0‑pre3 update, reviews technical articles on MySQL cloning, OceanBase indexing, data replication, charset issues, and connection‑pool design, recaps recent conferences, and previews upcoming OB Cloud open class events.

DataReplicationMySQLOceanBase
0 likes · 8 min read
ActionTech Open Source Community Weekly Newsletter – SQLE Updates, Technical Articles, and Events
Test Development Learning Exchange
Test Development Learning Exchange
Oct 28, 2023 · Databases

How Data Analysis Improves User Experience: Methods and Practical SQL Code Examples

This article explains ten data‑analysis techniques for enhancing user experience—such as behavior tracking, A/B testing, sentiment analysis, and personalization—and provides concrete SQL code snippets that illustrate how to import, query, filter, sort, aggregate, join, update, delete, and back up data in relational databases.

A/B testingSQLdata analysis
0 likes · 8 min read
How Data Analysis Improves User Experience: Methods and Practical SQL Code Examples
ITPUB
ITPUB
Oct 26, 2023 · Databases

Mastering Case Sensitivity Across Snowflake, Databend, MySQL, and PostgreSQL

This guide explains why case‑sensitivity issues arise in databases, how naming conventions can prevent them, and compares the behavior of Snowflake, Databend, MySQL, and PostgreSQL for database, table, column names and string literals, complete with practical examples and a concise checklist.

DatabasesDatabendMySQL
0 likes · 6 min read
Mastering Case Sensitivity Across Snowflake, Databend, MySQL, and PostgreSQL
Aikesheng Open Source Community
Aikesheng Open Source Community
Oct 26, 2023 · Databases

SQL Learning Course Outline and Book Giveaway Announcement

This announcement details a book giveaway sponsored by Tsinghua University Press and presents a comprehensive SQL learning curriculum covering SQLite, MySQL, query fundamentals, subqueries, joins, and advanced database features, complete with micro‑lecture videos and hands‑on exercises.

Book GiveawayDatabase tutorialMySQL
0 likes · 9 min read
SQL Learning Course Outline and Book Giveaway Announcement
MaGe Linux Operations
MaGe Linux Operations
Oct 23, 2023 · Databases

Master Oracle Daily Health Checks: Essential Commands for DB Stability

This guide details essential Oracle database daily inspection commands—covering instance status, tablespace health, resource usage, performance metrics, server CPU/memory/I/O checks, and security audits—to help DBAs ensure system stability and quickly diagnose issues.

Daily InspectionDatabase AdministrationOracle
0 likes · 11 min read
Master Oracle Daily Health Checks: Essential Commands for DB Stability
JD Retail Technology
JD Retail Technology
Oct 20, 2023 · Databases

Understanding Pagination Issues with ORDER BY and LIMIT in MySQL

This article examines why combining ORDER BY with LIMIT in MySQL pagination can produce duplicate rows on subsequent pages, analyzes the optimizer’s priority‑queue behavior introduced in version 5.6, and presents practical solutions such as using unique sort keys, adding ID ordering, and understanding deep‑pagination limitations.

LIMITMySQLOrder By
0 likes · 8 min read
Understanding Pagination Issues with ORDER BY and LIMIT in MySQL
dbaplus Community
dbaplus Community
Oct 18, 2023 · Databases

Doris vs ClickHouse: Which Database Delivers Faster Writes and Queries?

This article presents a systematic performance comparison between Doris and ClickHouse, covering data ingestion speed, SQL syntax differences, hardware impact, and detailed query benchmarks across multiple scenarios, ultimately revealing that each system excels in different use cases.

Big DataClickHouseDatabase Comparison
0 likes · 15 min read
Doris vs ClickHouse: Which Database Delivers Faster Writes and Queries?
Java Architect Essentials
Java Architect Essentials
Oct 17, 2023 · Databases

Understanding LEFT JOIN ON vs WHERE Conditions in SQL

This article explains how LEFT JOIN works in SQL, clarifying the difference between ON‑clause conditions that affect the join process and WHERE‑clause filters that operate on the resulting temporary table, using multiple example queries and visual illustrations.

LEFT JOINON clauseQuery Optimization
0 likes · 5 min read
Understanding LEFT JOIN ON vs WHERE Conditions in SQL
Top Architect
Top Architect
Oct 17, 2023 · Backend Development

Implementation and Comparison of Fluent MyBatis, Native MyBatis, and MyBatis‑Plus for Student Score Statistics

This article presents a typical requirement to calculate count, minimum, maximum, and average scores for three subjects in a student_score table, demonstrates how to fulfill it using raw SQL, then shows step‑by‑step implementations with Fluent MyBatis, native MyBatis XML, and MyBatis‑Plus code generation, and finally compares the three approaches highlighting their pros and cons.

Fluent-MyBatisJavaMyBatis
0 likes · 9 min read
Implementation and Comparison of Fluent MyBatis, Native MyBatis, and MyBatis‑Plus for Student Score Statistics
Selected Java Interview Questions
Selected Java Interview Questions
Oct 17, 2023 · Databases

SQL Techniques: Finding Duplicate Records, TRUNCATE vs DELETE, Primary vs Candidate Keys, Second Highest Salary, and Common Interview Queries

This article explains how to locate duplicate rows in a table, contrasts TRUNCATE and DELETE commands, clarifies the difference between primary and candidate keys, demonstrates queries for retrieving the second highest salary, and provides a collection of typical SQL interview questions with sample code.

Interview QuestionsPrimary KeySQL
0 likes · 9 min read
SQL Techniques: Finding Duplicate Records, TRUNCATE vs DELETE, Primary vs Candidate Keys, Second Highest Salary, and Common Interview Queries
Selected Java Interview Questions
Selected Java Interview Questions
Oct 11, 2023 · Databases

Understanding and Handling MySQL Deadlocks

This article explains MySQL deadlocks, describing common scenarios such as multi‑table updates, nested transactions, inconsistent index order, and concurrent index updates, provides a concrete banking transfer example, and outlines practical steps for monitoring, terminating, retrying, analyzing, and preventing deadlocks in production.

SQLTransaction
0 likes · 9 min read
Understanding and Handling MySQL Deadlocks
DaTaobao Tech
DaTaobao Tech
Oct 11, 2023 · Big Data

Fundamental Data Skills and Complex Query Techniques in MaxCompute

The article teaches developers essential MaxCompute data‑processing skills—from creating and naming tables, handling strings and dates, and writing basic SELECTs, joins, and aggregations, to employing advanced techniques such as temporary tables, CTEs, partitioning, and map‑join hints for efficient complex queries.

Data EngineeringETLMaxCompute
0 likes · 15 min read
Fundamental Data Skills and Complex Query Techniques in MaxCompute
Aikesheng Open Source Community
Aikesheng Open Source Community
Oct 9, 2023 · Databases

Using MySQL Offline Mode to Disconnect Client Connections

This article explains how MySQL's offline_mode variable and the pt‑kill tool can be used by DBAs to place a server in maintenance mode, instantly dropping non‑privileged client connections, preventing new ones, and providing a safe way to perform maintenance or backups.

Database MaintenanceMySQLOFFLINE_MODE
0 likes · 8 min read
Using MySQL Offline Mode to Disconnect Client Connections
Alibaba Cloud Big Data AI Platform
Alibaba Cloud Big Data AI Platform
Oct 9, 2023 · Big Data

How We Cut MaxCompute Costs Using Information Schema Insights

This article details how a fast‑growing HR SaaS company analyzed MaxCompute billing spikes, identified five key cost drivers, leveraged tenant‑level Information Schema to extract task metadata, applied SQL‑based cost formulas, and implemented targeted optimizations that stabilized their cloud data‑processing expenses.

Big DataInformation SchemaMaxCompute
0 likes · 10 min read
How We Cut MaxCompute Costs Using Information Schema Insights
dbaplus Community
dbaplus Community
Oct 8, 2023 · Databases

How to Optimize Pagination for Massive MySQL Tables with Sharding

When a single MySQL table grows to millions of rows, offset‑based pagination becomes painfully slow, so this article explains why, measures the performance impact, and presents three practical sharding‑aware pagination strategies—including global query, jump‑page prohibition, and a two‑step query method—along with concrete SQL rewrites and optimization tips.

MySQLPerformanceSQL
0 likes · 16 min read
How to Optimize Pagination for Massive MySQL Tables with Sharding
Liangxu Linux
Liangxu Linux
Oct 2, 2023 · Databases

Essential MySQL Optimization Tips: From EXPLAIN to Index Strategies

This guide presents a comprehensive set of MySQL performance‑tuning techniques—including proper use of EXPLAIN, limiting IN lists, selecting specific columns, avoiding costly ORDER BY RAND(), choosing UNION ALL over UNION, distinguishing IN from EXISTS, employing full‑text indexes, respecting left‑most prefix rules, and leveraging FORCE INDEX or STRAIGHT_JOIN—to help developers write faster, more efficient queries.

IndexingMySQLOptimization
0 likes · 12 min read
Essential MySQL Optimization Tips: From EXPLAIN to Index Strategies
dbaplus Community
dbaplus Community
Sep 27, 2023 · Databases

Understanding MySQL Locks: Which Queries Actually Acquire Locks?

This article breaks down MySQL's complex locking mechanisms—global, table, and row locks—explaining how different SELECT statements, transaction isolation levels, and index types affect lock acquisition, and provides practical test scripts and visual examples to help developers master lock behavior.

InnoDBIsolationLevelLocks
0 likes · 14 min read
Understanding MySQL Locks: Which Queries Actually Acquire Locks?
vivo Internet Technology
vivo Internet Technology
Sep 27, 2023 · Big Data

Horizontal Scaling of Hive Metastore Service at Vivo: Evaluation, TiDB Migration, and Lessons Learned

Vivo’s big‑data team horizontally scaled its Hive Metastore by evaluating MySQL sharding (Waggle‑Dance) against a TiDB migration, ultimately adopting TiDB, which after a synchronized cut‑over delivered ~15% faster queries, 80% DDL latency reduction, linear scaling, low resource use, and valuable operational lessons.

Big DataHive MetastoreSQL
0 likes · 19 min read
Horizontal Scaling of Hive Metastore Service at Vivo: Evaluation, TiDB Migration, and Lessons Learned
JD Cloud Developers
JD Cloud Developers
Sep 27, 2023 · Databases

How to Design Effective MySQL Indexes for Service Log Queries

This article explains how to create optimal MySQL indexes for a service_log table based on various search conditions, covering single‑column, composite, full‑text, prefix, and covering indexes, along with best practices, index size considerations, and practical SQL examples.

Full-Text SearchMySQLSQL
0 likes · 19 min read
How to Design Effective MySQL Indexes for Service Log Queries
Architecture Digest
Architecture Digest
Sep 26, 2023 · Backend Development

Comparative Implementation of a Student Score Statistics Query Using Fluent Mybatis, Native Mybatis, and Mybatis Plus

This article demonstrates how to implement a statistical query on a student_score table—calculating count, min, max, and average scores per term and subject—using Fluent Mybatis, native Mybatis, and Mybatis‑Plus, compares their code complexity, and provides code generation settings for each framework.

Fluent-MyBatisJavaORM
0 likes · 9 min read
Comparative Implementation of a Student Score Statistics Query Using Fluent Mybatis, Native Mybatis, and Mybatis Plus
ITPUB
ITPUB
Sep 26, 2023 · Databases

Why PostgreSQL Shows InitPlan and One‑Time Filter in Self‑Join Queries

This article walks through a puzzling PostgreSQL self‑join query, shows how different alias placements change the execution plan, explains the meaning of InitPlan and One‑Time Filter nodes, and demonstrates their impact with concrete examples and EXPLAIN output.

InitPlanOne-Time FilterPostgreSQL
0 likes · 11 min read
Why PostgreSQL Shows InitPlan and One‑Time Filter in Self‑Join Queries
dbaplus Community
dbaplus Community
Sep 24, 2023 · Databases

How Oracle 23c’s Converged Database Simplifies Multi‑Model Development

Oracle 23c turns the converged database vision into reality by unifying relational, document, and graph data under a single SQL engine, offering built‑in microservice support, lock‑free reservations, immutable tables, and an integrated SQL firewall to reduce architecture complexity and development cost.

23cConverged DatabaseDatabase Features
0 likes · 8 min read
How Oracle 23c’s Converged Database Simplifies Multi‑Model Development
Aikesheng Open Source Community
Aikesheng Open Source Community
Sep 22, 2023 · Databases

SQLE 2.2309.0-pre4 Release Notes – New Features, Rule Knowledge Base, and Full Release Information

The SQLE 2.2309.0-pre4 release introduces an enterprise‑level SQL lifecycle management panel, a rule knowledge base, new TDSQL audit rules, and intelligent metadata scanning tasks, while providing links to the repository, documentation, and demo environments for both community and enterprise editions.

Database AuditingMySQLRule Knowledge Base
0 likes · 8 min read
SQLE 2.2309.0-pre4 Release Notes – New Features, Rule Knowledge Base, and Full Release Information