BigQuery Migration · London
BigQuery Migration in London
Migrating London organisations onto BigQuery, where the assumption that costs most is that standard SQL simply ports. Dialects differ in date handling, type coercion, window behaviour and a hundred smaller details — and the queries that fail outright are less trouble than the ones that run and return a slightly different answer.
Why this comes up
The problem
The queries were translated, they all execute, and one report's totals differ from the old system by two per cent.
What you get
What we deliver
- Dialect differences catalogued against the constructs your queries actually use
- Results compared row by row rather than checked for successful execution
- Data model revisited, since a columnar store rewards different structures
- Nested and repeated fields used where they suit the data better than joins
- Partitioning and clustering designed during migration rather than retrofitted
- Parallel running until reconciliation across a full reporting cycle is clean
Want this scoped for your business in London?
Thirty minutes, no charge, no sales script. You leave with a written summary of what bigquery migration would actually involve — whether or not you use us.
Working in London
London
London clients usually come to us because they want senior people actually on their project rather than a large agency's B team, and because Midlands rates buy considerably more delivery per pound.
Clients here are usually replacing an agency, and want senior people on the work at rates that are not Central London rates.
Sectors we work with in London
- Financial Services
- Professional Services
- Technology
- Media
- Hospitality
- Retail
What we work with
Technologies and platforms
- BigQuery
- SQL
- dbt
- Google Cloud
Who we work with
Industries we serve
- Retail
- Media companies
- Technology companies
- Financial services
- Marketing agencies
Why us
Why London businesses choose Asionis
- Projects typically launched within 4–8 weeks
- No long-term contracts required
- All team members UK-based
- Dedicated account manager and development team
- Transparent reporting with monthly performance metrics
- Scalable from startup to enterprise
How we work
- Step 1
Free consultation
A 30-minute call to understand the problem. You keep the written summary either way.
- Step 2
Proposal
Scope, timeline and a fixed price, in writing, before anything starts.
- Step 3
Build
Short cycles with regular check-ins, so you see progress rather than hear about it.
- Step 4
Launch and support
We handle the go-live and stay available afterwards.
Other services in London
Looking for the full picture? See our BigQuery Migration services, everything we do in London or browse everything we do.
BigQuery Migration in London — common questions
- Which SQL differences cause the most trouble?
- Date and timestamp handling, implicit type conversion and null behaviour in aggregates. These rarely produce errors — they produce results that are quietly different, which is why comparing output matters more than confirming that everything ran.
- Should the data model change?
- Frequently, yes. Structures designed for a row-based system with expensive joins may be better expressed with nested fields here, and carrying the old model across means the platform's strengths go unused while its cost model applies regardless.
- How thoroughly should results be compared?
- To the row where volume permits, and to aggregate totals with distribution checks where it does not. A summary comparison passes when a small subset differs, and a small subset differing is exactly the failure that surfaces months later in a board pack.
- How long should both systems run?
- Through at least one complete reporting cycle with reconciliation at each stage. That period is what converts confidence from an assertion into evidence, and it gives the teams who depend on the numbers time to raise discrepancies while there is still something to compare against.
- Do you work with businesses across Greater London?
- Yes. We are based in Leicester, United Kingdom and work with clients throughout London, including London and the surrounding Greater London area. Most collaboration happens remotely, and we travel for kick-offs and key milestones.
- What kind of London businesses do you usually work with?
- Clients here are usually replacing an agency, and want senior people on the work at rates that are not Central London rates. Beyond that we work across Financial Services, Professional Services, Technology, Media, Hospitality and Retail.
- Do you cover the areas around London?
- Yes — we work throughout London, including Reading, Milton Keynes, Cambridge, Brighton. London is an urban area of roughly 9,000,000+, and we take on work across the wider Greater London region rather than the city boundary alone.
Talk to us about BigQuery Migration in London
A 30-minute call with someone who would actually work on it. No sales script, no obligation.
- Projects typically launched within 4–8 weeks
- No long-term contracts required
- All team members UK-based
- Dedicated account manager and development team
- Transparent reporting with monthly performance metrics
- Scalable from startup to enterprise