The JusDB Database Engineering Blog

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.

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.

Leverage MySQL 8.4 InnoDB parallel DDL for faster schema changes. Learn parallel index creation, online DDL improvements, and reduced maintenance windows.

MySQL architecture from query parser to disk: optimizer pipeline, InnoDB buffer pool, redo log, and storage internals every production DBA needs in 2026.

Configure auto_explain to automatically log EXPLAIN output for slow PostgreSQL queries. Covers log_analyze, log_buffers, sample_rate, JSON format, and RDS setup.

Use hypopg to test how a new PostgreSQL index would affect query plans before building it. Includes install, hypothetical index creation, EXPLAIN workflow, and index sizing.

Master PostgreSQL window functions: ROW_NUMBER, RANK, SUM OVER, LAG/LEAD, moving averages, and frame clauses. Real SQL examples for analytics and reporting queries.

Understand how PostgreSQL TOAST stores large columns, diagnose TOAST bloat with SQL, choose the right storage strategy, and use LZ4 compression in PG14+.

Learn how to use pgBadger to analyze PostgreSQL logs, find slow queries, and automate daily reporting. Includes postgresql.conf setup, cron automation, and RDS tips.

Use PostgreSQL tablespaces to distribute tables and indexes across NVMe, SSD, and archive storage. Covers creation, ALTER TABLE SET TABLESPACE, monitoring, and backup.