Data Engineering & Performance

Database Performance & Schema Scaling

Eliminate slow queries, database connection bottlenecks, and concurrency locks to scale high-throughput data workloads reliably.

Written scope and a fixed-scope proposal. No sales calls.

The buyer this is written for

Role
Engineering Lead, CTO, or Lead Database Architect
Organisation
A growing web application or business experiencing slow response times, database CPU spikes, locking, or query timeouts
What triggers the search
Application queries timing out under load, database hosting tier costs escalating rapidly, or a major schema migration that cannot afford downtime.

What is actually going wrong

Slow queries causing 504 timeouts and high server CPU

Unindexed table scans, unoptimized joins, and N+1 query patterns cause latency to spike as table sizes grow into millions of rows.

Connection pool exhaustion and lock contention

High-frequency writes or unindexed updates lock rows, creating queue cascades that exhaust database connection pools and bring down the web API.

Fear of migrating large live production tables

Altering schema or backfilling columns on live tables risks table locks and downtime. Critical schema improvements get postponed indefinitely.

Delivered in the engagement

  • Comprehensive query execution plan profiling and slow query elimination
  • Strategic indexing and query rewrites for sub-100ms response times
  • Connection pooling and read/write splitting architecture recommendations
  • Zero-downtime, non-blocking schema migration scripts with automated rollback
  • Caching layer integration for high-frequency read hotspots
  • Database health monitoring baseline and query regression tests

The sequence

  1. Profile slow queries and execution plans

    Analyze database metrics, slow query logs, and EXPLAIN execution plans to pinpoint exact index misses and lock bottlenecks.

  2. Optimize indexes and query logic

    Implement composite, partial, and covering indexes. Rewrite inefficient joins and subqueries to eliminate sequential table scans.

  3. Decouple write hotspots and connection pools

    Introduce connection pooling and asynchronous queueing for write-heavy spikes, protecting the primary database thread pool.

  4. Execute zero-downtime migrations

    Apply expand-and-contract non-blocking schema migrations with dual-write validation before cutting over live application traffic.

Engagements that prove this

Every claim below is drawn from a recorded engagement. Each links to its full case study, including the trade-offs that were accepted.

Primary evidence

Advanced MD

Healthcare Industry • Aug 2023 • JavaScript, MySQL, PHP, WordPress

Healthcare practice management platform requiring high-throughput data access and strict schema integrity.

  • Optimized complex healthcare relational data models eliminating query timeouts
  • Strict system boundary compliance protecting sensitive data flows
  • Sub-second search and lookup latency across large catalog datasets
Read the full case study →

Jewish Data

Information Services Industry • Oct 2014 • CodeIgniter, Git, JavaScript, MySQL, PHP

Large-scale archival search database handling massive record lookups and genealogical indexing.

  • Optimized MySQL query index pipelines for fast text search across millions of records
  • Reduced database server memory footprint during bulk search queries
  • Git-backed schema versioning ensuring reproducible data structures
Read the full case study →

Capital MPO

Transportation Industry • Feb 2018 • JavaScript, MySQL, PHP, WordPress

Document management repository with high-volume concurrent retrieval.

  • Decoupled asset storage reducing web and database thread pool saturation by 75%
  • Automated data consistency checks eliminating orphaned record anomalies
Read the full case study →

Wider evidence: Platform Hardening draws on 105 recorded engagements, from a corpus of 106 documented projects.

Answered directly

Can database optimization happen without downtime?

Yes. We use concurrent index creation, read replicas, and expand-and-contract migration patterns that apply structural improvements without locking active tables.

Which databases do you support?

We specialize in PostgreSQL, MySQL, Supabase, Cloudflare D1/SQLite, and related relational engines.

How quickly can we see improvements in query times?

High-impact index additions and query rewrites typically deliver 50–90% latency reductions within the first phase of the engagement.

This page answers

  • How do I fix slow SQL queries in PostgreSQL or MySQL?
  • Who can optimize our database performance and eliminate connection timeouts?
  • How to do zero downtime database schema migrations on large tables?
  • What is the best way to resolve database lock contention under high traffic?
  • Database performance audit and query tuning consultant

Start a written project inquiry

Describe your database stack (PostgreSQL, MySQL, etc.), dataset size, current query bottlenecks or locking symptoms, and performance goals.

You describe the problem in writing. You receive a written scope, an approach, and a fixed-scope proposal.