database

Understand ProxySQL hostgroups: what they are, how they route MySQL traffic, common use cases, pitfalls, Galera cluster integration, and running multiple ProxySQL instances across data centers.

Learn how to use ProxySQL as a connection pooler between PHP applications and MySQL, dramatically reducing connection overhead and improving database scalability.

Real senior Python interview questions from a top outsourcing company in Vietnam — covering data structures, memory management, async concurrency, database optimization, and code quality.

A structured learning path through the internals of modern databases — from storage engines and B-Trees to transactions, indexing, query processing, and distributed systems.

Master advanced SQL features: window functions for rankings and running totals, CTEs for readable query composition, recursive queries for hierarchical data, and essential functions for real-world analytics.

Deep dive into Galera Cluster internals — the wsrep API, write-set replication, certification-based conflict resolution, node states, flow control, quorum mechanics, and SST vs IST recovery.

Learn how Yii2 talks to databases — configure db connections, write migrations, perform CRUD with Active Record, define model relations, build complex queries with Query Builder, and wrap operations in transactions.

Understand MySQL binary log replication from the ground up — how async and semi-sync replication work, what GTIDs are and why they matter, replication lag causes, and the failure modes that led to Galera Cluster.

Master MySQL high availability from replication basics to multi-master Galera clusters, Percona XtraDB Cluster, ProxySQL query routing, backup strategies, and production monitoring with PMM.

Compare three modern TypeScript ORMs side by side: Prisma, TypeORM, and Drizzle. Learn their architectures, query patterns, migration strategies, performance characteristics, and when to use each with practical examples.