Databases
PostgreSQL, MySQL/MariaDB and Redis - connections, locks, slow queries, backups and the failures that take a database offline.
Sub-topics
PostgreSQL
21Connections, vacuum, wraparound and the Postgres-specific gotchas.
MySQL & MariaDB
23InnoDB, collations, packet limits and the MySQL family's sharp edges.
Performance & Indexing
13Slow queries, missing indexes, locks and deadlocks.
Redis & Caching
4Eviction, persistence, memory limits and cache invalidation gone wrong.
Backup & Recovery
2Dumps, restores, replication lag and disaster recovery.
54 articles · showing 1-9 (page 1 of 6)
Metering, model routing and the regression suite that stops your agent rotting
Two questions decide whether an AI feature survives its first year: does each request make money, and will a prompt edit break something silently? An append-only credit ledger, two-tier routing, and a suite that asserts question-to-metric mappings are the answers.
Six ways Android will eat your background service, and what actually worked
A broadcast receiver is a lie, WAL journalling wedged openDatabase on OxygenOS, and one polite database close in a WorkManager teardown silently stopped the whole gateway. Six real failure modes from a production Android SMS gateway, and the fix for each.
What bench migrate actually does, and the rollback you'll wish you had
Every patch commits as it completes and records itself as applied. So a migration that fails halfway is not a failed migration, it is a half-finished one, and re-running will not undo it. Here is the recovery, with real commands.
Shipping a business agent on WhatsApp: templates, webhooks and the 24-hour window
The in-app chat panel was good and nobody opened it. Putting the agent on WhatsApp means the Cloud API's template rules, idempotent webhooks, per-tenant scheduled jobs, alert hysteresis, and testing that Sheng routes to the right metric.
Find the Query Killing Your ERPNext: A MariaDB Slow Query Log Playbook
Your ERP is slow and three queries are responsible. Configure the MariaDB slow query log properly, run pt-query-digest, and read the numbers that tell you whether it is an index problem or a hardware problem.
Building RAG Over Your ERP Data: The Architecture That Actually Survives Production
Most ERP chatbots fail the moment someone asks for a total. Here is the two-plane architecture, the hybrid retrieval SQL, the reranking step and the permission model that separate a demo from a system finance will actually trust.
Indexes That Actually Work: A Field Guide to tabGL Entry and tabStock Ledger Entry
ERPNext ships mostly single-column indexes, which are the wrong shape for the reports killing your server. Real EXPLAIN output, the leftmost prefix rule, key_len maths, and the composite indexes that fix ERP reports.
Why we did not point an LLM at ERPNext: building a semantic layer for a business agent
Text-to-SQL against a real accounting schema produces confidently wrong numbers, because ERPNext stores revenue in the general ledger, stock valuation in the stock ledger, and gross margin nowhere at all. Here is the metric catalog and catalog-first hybrid engine we built instead.
bench backup Is Not a Backup Strategy: Binlogs and Point-in-Time Recovery for ERPNext
A nightly dump means losing a full day of invoices. Set up mariadb-backup plus binary logs, then walk a real recovery: finding the binlog position of a bad bulk cancel and replaying up to the second before it.