The JusDB Database Engineering Blog

StarRocks 4.1 makes tablet layout adaptive: Range distribution, automatic splitting at 10 GB, and 100 GB tablets. When to enable it, and what it costs.

PostgreSQL 19 Beta 1 (June 4, 2026) brings parallel autovacuum, the native REPACK command for online table rebuilds, 2x faster inserts under foreign-key load, online logical replication without a restart, WAIT FOR LSN for read-your-writes consistency, and default changes (JIT off, lz4 TOAST, RADIUS removed). A DBA-focused walkthrough of what changed and what to test before GA.

A top-down playbook for high-performance MongoDB: measure with the profiler and explain(), model for access patterns, index by the ESR rule, keep the working set in the WiredTiger cache, pool connections, and scale reads with secondaries and sharding — with flow diagrams for each layer.

A step-by-step guide to migrating an on-premises Microsoft SQL Server database to Amazon RDS for SQL Server — covering native backup/restore via S3 with the rds_restore_database stored procedure, AWS DMS full-load + CDC for near-zero downtime, option group and IAM setup, cutover, and post-migration hardening.

A repeatable, top-down method for tuning PostgreSQL: measure with pg_stat_statements, read plans with EXPLAIN (ANALYZE, BUFFERS), fix queries and indexes before parameters, then tune memory, I/O, WAL, connection pooling, and autovacuum — with a ready-to-adapt postgresql.conf baseline.

Walk through PostgreSQL's multi-process architecture, shared/local memory layout, page-organized storage, MVCC tuple versioning, the WAL write path, the query execution pipeline, and physical + logical replication — all with ASCII flow diagrams that show how data and control actually move through the system.

The decision matrix for the three Azure SQL flavors: eight constraints (cross-DB queries, SQL Agent, CLR, linked servers, networking, licensing…) that pick Managed Instance vs Azure SQL Database vs SQL Server on Azure VM, with a cost comparison and migration paths.

Production setup of Ola Hallengren's SQL Server Maintenance Solution: the four jobs that matter, FULL/DIFF/LOG backup cadence for your RPO, DBCC CHECKDB scheduling, IndexOptimize tuning, encryption, and CommandLog-based alerting.

Read SQL Server wait stats like a senior DBA: the four DMV sources, the eight wait types that cover 95% of incidents (PAGEIOLATCH, LCK_M, CXPACKET, WRITELOG…), and the remediation for each. A 30-minute diagnostic workflow from page to plan.

Production-ready MySQL Group Replication deployment guide. Learn cluster sizing, monitoring setup, performance tuning, and disaster recovery planning.

Deep dive into InnoDB storage engine internals. Understand buffer pool, redo log, undo log, change buffer, and adaptive hash index for expert-level MySQL optimization.

Everything you need to know about MySQL: storage engines, replication topologies, performance tuning, and cloud deployment. From basics to advanced optimization.