SQL query optimization for startups and SMEs
I review complex queries, stored procedures and reporting SQL to cut wasted work, simplify execution plans and make the data layer easier to maintain.
- Complex queries nobody wants to touch
- Stored procedures doing too much work
- Reporting SQL that drags under load
- Safer refactoring with before and after proof
Targeted query-level improvements with measurable results
Stored procedure rewrites
Refactor complex stored procedures that have grown organically: simplify logic, eliminate cursors, and restructure for set-based operations.
Reporting SQL
Optimize the query layer behind SSRS, Power BI, and custom dashboards. Reduce scan times and make reports responsive again.
ETL pipeline queries
Improve data load performance, optimize merge operations, and fix bottlenecks in SSIS packages or custom ETL SQL.
Parameter sniffing & regressions
Diagnose and fix queries that perform inconsistently due to parameter sniffing, plan cache pollution, or statistics drift.
Complex joins & subqueries
Simplify deep join chains, correlated subqueries, and nested CTEs that cause exponential performance degradation.
Query pattern review
Audit your most resource-intensive queries as a group, identify common anti-patterns, and prioritise fixes by business impact.
Understand before rewriting
I don't start rewriting queries blindly. First I understand the business context, the data volumes, the access patterns, and the constraints. Then I optimize with a clear understanding of what the query is supposed to achieve and how it will be used.
- Analyse execution plans and resource consumption.
- Understand business logic before touching a line of SQL.
- Rewrite with set-based patterns and proper indexing support.
- Validate with production-representative data and load.
Common questions about query optimization
How do you approach query optimization?
I start by analysing execution plans, identifying the most expensive operators, and understanding the data distribution. Then I rewrite queries, adjust indexes, and validate improvements with before/after metrics.
Can you optimize stored procedures without breaking the application?
Yes. I work within the existing interface contracts, with the same parameters and result sets, so the application layer doesn't need changes unless we explicitly agree otherwise.
What kind of improvements should I expect?
It depends on the root cause. I've seen queries go from minutes to sub-second with the right index and rewrite. I always provide measurable evidence of the improvement.
Do you handle reporting SQL and ETL queries too?
Yes. Heavy reporting queries and ETL pipelines are some of the most common optimization targets. I work on the query layer that feeds dashboards, SSRS reports, and data pipelines.
Need faster queries?
Describe what's slow. I'll review the situation, tell you what I'd do, and give you a clear scope and timeline.
