The November 2017 DB‑Engines ranking shows Oracle, MySQL and Microsoft SQL Server still dominate the top three, while Splunk and HBase swap places, PostgreSQL climbs to fourth with a 54.1% year‑over‑year gain, and the list is based on five popularity factors such as search engine queries, job postings, and Stack Overflow activity.
This article shares practical, step‑by‑step methods for programmers to improve code quality, reduce endless bug fixing and overtime, and cultivate disciplined habits such as focused planning, thorough requirement analysis, ignoring unnecessary quality checkpoints, writing readable code, and deliberate practice.
This guide walks developers through deploying a WeChat Mini Program with PHP by authorizing Tencent Cloud on the WeChat Public Platform, installing the developer tools, importing the wafer2‑quickstart‑php demo from GitHub, configuring credentials, and uploading the code to create a ready‑to‑use cloud environment.
The iQIYI recommendation system combines a two‑stage pipeline of recall and ranking, evolving from logistic regression to a GBDT‑FM‑DNN ensemble, using online feature storage, extensive feature engineering, and configurable strategies to deliver personalized video suggestions while addressing feature drift and multi‑objective business goals.
This guide compiles the most frequent problems encountered when installing the TDH Community Edition—such as hostname configuration, logical volume creation errors, service startup failures, firewall settings, and license issues—and provides clear step‑by‑step solutions to help users avoid and resolve these obstacles.
This article describes how Ctrip built a container‑cloud platform by dividing infrastructure into "under‑water" (foundations) and "over‑water" (developer‑facing practices), evolving through three architectural stages, and addressing networking, monitoring, resource fragmentation, JVM tuning, Dockerfile management, and a plugin‑based extension model to support DevOps and micro‑service deployments.
This article explains why Weave's FastDb mode can cause network interruptions on CentOS 7 VMs, analyzes the underlying kernel bugs and UDP PMTU probing issues, and provides practical solutions such as kernel upgrades, disabling UFO, and adjusting MTU settings.
The article explains Android image downsampling, comparing built‑in nearest‑neighbour and bilinear methods with higher‑quality bicubic and Lanczos resampling, detailing their implementation, performance trade‑offs, and visual results, and advises choosing the fastest method for simple cases or the more intensive algorithms when superior image fidelity is required.
This article explains a practical pipeline for extracting dominant colors from product images—using image resizing, MeanShift and FloodFill segmentation, region merging, Gaussian weighting, selection, and CIELab-based tagging—enabling accurate color-based search in e‑commerce platforms.
This article explains symmetric and asymmetric encryption, the key‑distribution problem, hybrid cryptosystems, one‑way hash functions, message authentication codes, digital signatures, public‑key certificates, and compares these cryptographic methods in detail.
This article describes how the OPS team designed and implemented a private‑cloud Elasticsearch service using Mesos for resource management, Docker containers orchestrated by Marathon, and a suite of monitoring, self‑service configuration, and continuous deployment tools to improve resource utilization and operational efficiency.
This article explains the purpose of each log level, when to write logs, performance impacts, and concrete best‑practice patterns for INFO, DEBUG, WARN and ERROR in Java applications, providing actionable templates and configuration tips to build a robust logging system.
This article introduces ten common Linux kernel processes, explaining their roles—from memory management with kswapd0 to I/O handling by aio—helping operators and developers recognize and interpret the often‑bracketed system daemons that appear in ps listings and affect system performance.
This article introduces Python's string formatting operators, explains how %r converts values to strings and %d formats integers, and demonstrates their usage with concrete code examples and output, guiding beginners through building formatted messages step by step.
To handle Meituan’s 16 million daily orders and massive traffic spikes, the company built an automated operations platform that combines a real‑time business dashboard, health‑scoring core link, automated protection switches, and full‑link stress‑testing, enabling automatic anomaly detection, root‑cause diagnosis, capacity planning, and self‑remediation without manual intervention.
This article explains the fundamentals of ROC curve construction, the calculation of AUC, compares ROC with PR curves, and provides step‑by‑step examples—including a medical diagnosis scenario and threshold adjustments—to help readers accurately evaluate binary classification models.
This article walks through diagnosing a packet‑drop issue in OpenStack Neutron security groups, detailing network architecture, packet capture, iptables chain analysis, rule addition, and validation steps to restore communication between Linux Director and virtual machines.
This article explains how Python's eval can execute arbitrary code, demonstrates multiple bypass techniques—including __import__, __builtins__ manipulation, and object subclass exploitation—and shows how to safely restrict eval using whitelist globals or ast.literal_eval to prevent code injection and denial‑of‑service attacks.
The article analyzes the limitations of general‑purpose CPUs for deep‑learning workloads, explains how semiconductor scaling and memory‑bandwidth constraints drive the shift toward specialized heterogeneous processors such as GPUs, FPGAs, and ASICs, and discusses the design trade‑offs of embedded versus cloud AI accelerators.
This article introduces a collection of lesser‑known Linux commands—such as sudo !!, python -m SimpleHTTPServer, mtr, Ctrl+x+e, nl, shuf, ss, last, curl ifconfig.me, tree, and pstree—explaining their purpose, typical use‑cases, and providing concrete examples to help both desktop users and system administrators work more efficiently.
