--- tytul: "E-commerce Data Warehouse: Profit Analytics" opis: "Ad platforms count revenue, the store counts product cost, the warehouse counts returns. One database joins them so you see profit per order and channel." adres: https://justidea.agency/en/services/marketing-agency/ecommerce-data-warehouse/ serwis: "JustIdea Agency" jezyk: pl zrodlo: automatyczny odpowiednik strony HTML, generowany przy każdym buildzie --- [Home](https://justidea.agency/en/)/[Services](https://justidea.agency/en/services/)/[Digital marketing agency](https://justidea.agency/en/services/digital-marketing-agency/)/Data warehouse Data warehouse [4.96 224 reviews](https://justidea.agency/en/justidea-reviews/) # E-commerce data warehouse that shows profit The ad platform counts revenue, the store counts product cost, the warehouse counts returns and accounting counts something else again. An ecommerce data warehouse is one database in which those four numbers sit side by side and can be compared. We bring in data from the ad platforms, the online store, the warehouse and the ERP. Then we agree one definition of an order and build a report with margin after product cost, returns and ad spend. We call it Profit Analytics, and it is where the budget decision starts. Book a call about your store's margin How we price it ** One definition of an order Before we count anything, we agree with you what an order is and how returns are treated. Without that one decision four systems give four different truths. ** Your data stays with you The warehouse sits in your own Google BigQuery account. When the work ends you keep the database, the models and the full history, not access to someone else's tool. ![Four data sources brought into one warehouse](https://justidea.agency/assets/ill-hurtownia.svg) ![Google BigQuery](https://justidea.agency/assets/znak-bigquery.svg) ![Looker Studio](https://justidea.agency/assets/znak-looker.svg) 8-13 wks from access to the report Trusted by ![LPP](https://justidea.agency/obrazy/lpp-logo-2-b64d3a02.svg) ![House](https://justidea.agency/obrazy/logo-house-c706eeae.svg) ![Toyota](https://justidea.agency/obrazy/toyota2-1-63c6570a.webp) ![Fame MMA](https://justidea.agency/obrazy/fame-ffb4e0d0.webp) ![Surf Inc.](https://justidea.agency/obrazy/surfinc-91e5b73d.webp) ![LyoFood](https://justidea.agency/obrazy/lyo-cb899d46.webp) ![ExpertSender](https://justidea.agency/obrazy/expert-ca00548d.webp) ![Purinova](https://justidea.agency/obrazy/purinova-217da6ab.webp) ![Mennica Gdańska](https://justidea.agency/obrazy/mennica-98166c12.webp) ![Group IB](https://justidea.agency/obrazy/group-ib-b711171e.webp) ![Smart Kids Planet](https://justidea.agency/obrazy/smart-kids-151311c5.webp) ![SuperSonic](https://justidea.agency/obrazy/supersonic-a35404fe.webp) ![Wierzynek](https://justidea.agency/obrazy/wierzynek-1-d027e7cc.webp) ![RegoBis](https://justidea.agency/obrazy/regobis-a8b446e3.webp) Technology partners ![Google Premier Partner](https://justidea.agency/obrazy/google-premier-partner-d0211fa8.svg) ![Meta Business Partner](https://justidea.agency/obrazy/meta-partner-300x172-8802cc64.webp) ![Allegro Ads Partner](https://justidea.agency/obrazy/allegro-ads-300x179-75604353.webp) ![HubSpot Certified Partner](https://justidea.agency/obrazy/hubspot-partner-300x145-34b60f9f.webp) Starting point ## Why does data from different sources give four different results? Because each system counts a different thing and none of them knows about the others. Below are four situations that come up at the first meeting, once we put your reports side by side. ** ### Every channel claims the same sale The sum of revenue from the ad platforms is often higher than the store's revenue. Not because anyone is lying, but because each platform counts in its own way and knows nothing about the rest. ** ### Returns never reach the report A campaign looks profitable until returns are subtracted. In some categories that is the difference between profit and loss, and it only shows up a few weeks later, once the returns are back in the warehouse. ** ### Product cost lives in another system The margin is in the ERP or a spreadsheet, the campaign result is in the ad platform. Putting the two together is done by hand once a quarter, which is why decisions get made without it. ** ### The report is assembled by hand and out of date Every month someone gathers numbers from several systems into a spreadsheet and loses working days on it. The work is repetitive, so it can be automated, and yet it keeps coming back. Definition ### What is a data warehouse and why is it not an ordinary database? **A data warehouse is** one place that automatically receives data from ads, the store, the warehouse and company systems, organised so it can be joined. It is not a reporting tool but the layer beneath one: a report without it shows what one system sees, not what is happening in the business. We build it on Google BigQuery, a standard cloud platform rather than a closed system of our own: it is your warehouse and it stays with you, together with the data. Bringing data in from your systems A marketing data warehouse starts with ads: Google Ads, Meta, Allegro and GA4. On the sales side come the store, the ERP, the warehouse and returns. Each source has its own format and its own delay, so reconciling them is part of the job. On BigQuery, in your account The warehouse runs on Google BigQuery and belongs to you. You pay Google for it directly, and if you change agency you lose neither the data nor the history. One definition and one measure We agree what an order is, how we calculate contribution margin and what we do with returns. We take product cost per SKU if your store or ERP holds it, and if not, as a percentage of revenue agreed with you. A report you can sign off On top sits a report showing channels side by side and margin after product cost, returns and ad spend. It is the number you move budget on, not one you have to explain away. How we implement it ## Building a data warehouse for an online store We do not start with the database but with an audit of the sources: we check whether the data you want to join can be joined at all. Then come building the warehouse, the reports and the maintenance that keeps them refreshing on their own. 1. 1 ### Audit of sources and definitions 2-3 weeks What you have in which system, at what quality and with what delay. This is also where we agree the definition of an order and of margin, because without it the rest makes no sense. 2. 2 ### Building the warehouse 4-6 weeks A cloud account in your company's name, automatic data pulls from the sources, models joining sales with costs and returns. We pull ads and sales data with full history, while Analytics data starts from the day we connect the export, because Google does not hand over its history. 3. 3 ### Reports and rollout in the team 2-4 weeks The main report plus views per channel. On top of that, team training, because a report nobody can read changes no decision. 4. 4 ### Maintenance and development ongoing Sources change, APIs stop working, new channels arrive. Maintenance is mainly making sure the data keeps flowing and adding further views. Client reviews ## A project measured in quarters, whose effect the analyst sees first An e-commerce data warehouse starts to pay for itself when the first report contradicts a number from the ad platform, and that can be a few months after the contract is signed. Until then all you have to go on is what others say about JustIdea. Below are three profiles where clients write about us. 4.96 / 5 weighted average of 224 reviews across three platforms. Clients gave them, and each site below links to the profile with the full text of every review. [Read the reviews](https://justidea.agency/en/justidea-reviews/) [![Google](https://justidea.agency/assets/logo-google.svg) 4.97 / 5 156 reviews on our Google Business Profile See the profile](https://www.google.com/search?q=JustIdea+Agency+Krak%C3%B3w+opinie)[![Facebook](https://justidea.agency/assets/logo-facebook.svg) 5.0 / 5 33 reviews on our Facebook page See the profile](https://www.facebook.com/justidea.agency/reviews)[![Clutch](https://justidea.agency/assets/logo-clutch.svg) 4.9 / 5 35 B2B reviews, each verified in a call with the client See the profile](https://clutch.co/profile/justidea-agency) Certifications and partnerships ## Google, Meta and Allegro: statuses in the platforms that feed the data A warehouse is worth as much as the data flowing into it, and most of your ad spend and part of your sales run through these three systems. ### Google Premier Partner Google, top tier of the Google Partners programme Google Ads and Analytics are the biggest sources of cost and traffic data in most warehouses. The status confirms we run Google campaigns every day, so when the panel and the warehouse disagree, we can explain it, not just show it. ### Meta Business Partner Meta, partner programme for Facebook and Instagram Meta data is the most troublesome source in the whole warehouse: campaign results keep changing retroactively for several days after the event. We run Meta campaigns every day, so we know when a number in the warehouse has actually settled. ### Allegro Ads Partner Allegro, partner programme of the advertising platform Marketplace sales most often stay outside the profit account, because the data sits in a separate panel. We pull it into the same warehouse as your own store, so you see margin from Allegro and from the store in one report. Doubts before working together ## Benefits of a data warehouse versus doubts: four things we hear ### „We have GA4, why would we need a warehouse” GA4 sees behaviour on the site, knows neither product cost nor returns and keeps data for a limited time. The warehouse is a layer below, and it is what lets you calculate profit. One does not replace the other. ### „We are too small for a warehouse” That happens, and then we advise against it. A warehouse makes sense once a single badly placed chunk of ad budget costs more than a year of running it. The second threshold is the moment someone in the company spends a day a month stitching a report together from spreadsheets. ### „This is a six-month project” The first working report is usually in place six to ten weeks after the audit is complete. Expansion takes longer, but you do not have to wait for it to make decisions, because the most important channels go in during the first phase. ### „We already have a BI tool, it just needs connecting” A visualisation tool will not replace the data layer. If you already have a warehouse and are only missing models or reports, that is a shorter project and we price it that way. Limits of the service ## How does a data warehouse differ from analytics and from server-side tracking? Short answer Analytics answers what is happening on the site. The warehouse sits one layer below and answers how much of it is left in the till after product cost, returns and fees. Server-side tracking says HOW data leaves the site, and this service says what to do with it next. Implementation usually takes six to ten weeks. We connect ads, Analytics, the store and BaseLinker through ready-made connections, so access is enough and you do not need a developer on your side. The ERP and the warehouse management system need a data export from your own system, and we agree on that during the audit. The profit account then guides decisions on the ad budget, but on this page we do not run campaigns. It is a deliberate split: whoever builds the numbers should not be the only one taking credit for them. If you want both from us, we say so plainly when quoting and keep the report separate from the budget recommendation. The cost of storage and queries in the cloud is on your side and you pay it directly to the provider, not to us. Analytics data enters the warehouse through the export, not through a report from the interface, and that is why the numbers can differ from those in the interface. We show you that difference at the first meeting instead of explaining it three months later. ![Three layers of working with data: server-side sending, site analytics and a warehouse with a profit account; this service is the third layer](https://justidea.agency/assets/ill-hurtownia-trzy-warstwy.svg) ### This is the service - You want a profit account, not revenue from an ad platform. - Product cost, returns and fees need to go into one number. - The data sits in several systems and nobody joins it. - Scaling decisions cost more than the report itself. ### That is different work - Events on the site are counted wrongly: that is web analytics. - Data needs to leave the browser: that is a server-side implementation. - You want someone to run campaigns on these numbers: that is a separate service. Sources: [BigQuery in the Google Cloud documentation](https://cloud.google.com/bigquery/docs/introduction) · [Analytics export to BigQuery](https://support.google.com/analytics/answer/9358801) Watch before you ask for a quote ## The full talk on why ROAS does not tell you how much you earn Mateusz Haber at Event.Ecommerce.pl 3.0 (the talk is in Polish). Where the double-digit ROAS figures in agency reports come from, how POAS differs from MER and what a data warehouse really counts. The same method we implement for clients, presented to a room full of store owners. **![Mateusz Haber on stage at Event.Ecommerce.pl 3.0](https://justidea.agency/obrazy/wideo-roas-to-mit.webp) Watch the talk (in Polish) · 27 min Event.Ecommerce.pl 3.0 · October 2025** ![Mateusz Haber](https://justidea.agency/obrazy/mateusz-haber-5ab92683.png) „Stop dreaming of double-digit ROAS”, **Mateusz Haber**, CEO of JustIdea Agency and CEO of Surf Inc. [Watch on YouTube →](https://www.youtube.com/watch?v=NPmbLwnmjWU) How we price it ## How much does a data warehouse implementation cost Implementation starts from €1,230 net, and maintenance is a monthly subscription we quote together with it. Further sources, and data that first needs to be put in order, we quote after the audit. You pay the cloud cost separately and directly to Google, and how much depends on your data volume and query load. First step ### Source audit What you have, at what quality and whether it can be joined into one profit account. Custom quote report with a data map - Included: inventory of sources, assessment of data quality and completeness, a proposed definition of an order and of margin, and a quote for the implementation. I want the audit One-off ### Implementation A warehouse in your BigQuery account, automatic data pulls and the main report, which is Profit Analytics. from €1,230 project, 6-10 weeks - Included: cloud setup, connections to the sources, models joining sales with costs and returns, the main report and views per channel, and team training. I want this package Subscription ### Maintenance Keeping the data flowing, fixes after API changes and adding new views. Custom quote per month - Included: connection monitoring, fixes after changes on the providers' side and new report views on request. We quote a new data source separately, the same as additional sources at implementation. I want this package [See the analytics service](https://justidea.agency/en/services/marketing-agency/web-analytics/) FAQ ## Choosing an e-commerce data warehouse: questions before you decide **### Why does a store need a data warehouse if it has GA4?** GA4 describes user behaviour on the site and knows neither product cost, margin nor returns, and it keeps raw data for a limited time. A warehouse brings data from ads, the store, the warehouse and company systems into one place and lets you calculate profit rather than sessions. They are two different layers: GA4 is a source, the warehouse is where the sources meet. **### How much does a data warehouse implementation cost?** Implementation starts from €1,230 net as a one-off, and maintenance is a monthly subscription quoted with it. With more source systems, or data that first needs to be put in order, the figure grows and we give it after the audit. The source audit itself is a separate one-off order and ends with a data map and a cost estimate. On top of that comes the cloud cost, paid directly to the provider and dependent on usage. **### How long does a data warehouse implementation take?** Six to ten weeks from the end of the audit to the first working report, and most of that time goes not on building but on agreeing definitions and cleaning up data on the source side. Expansion to further channels and views then goes in stages and does not block you from using what is already in place. **### Does the data stay with us?** Yes. The warehouse sits in your Google BigQuery account, under your agreement with Google, and JustIdea has access granted by you. When the work ends you keep the database, the models, the reports and the full history. That is an important difference from tools where the data sits with the vendor and disappears along with the subscription. **### Which systems can the warehouse connect to?** On the marketing side Google Ads, Meta, Microsoft Ads, Allegro, GA4 and Search Console, and on the sales side Shopify, PrestaShop, WooCommerce, Shoper, IdoSell, Magento and BaseLinker, because these already have ready-made connections. We bring in the ERP and the warehouse management system through a data import that we agree with you. The difficulty is not the number of integrations but whether a given system exposes data at all, and whether an order can be identified in it unambiguously. That is what we check in the audit. **### How is this different from a Looker Studio report?** Looker Studio is a visualisation layer: it shows whatever it is given. Connected straight to the ad platforms, it repeats their limitations, including the same sale being counted by several channels. The warehouse is the layer underneath, and it resolves such conflicts before a number reaches the chart. We usually build the reports themselves in Looker Studio, but on the warehouse, not on the platforms. ## Data warehouse, ETL and data for business decisions ** ### What a data warehouse is, in one paragraph It is a database designed for analysis, not for day-to-day operations. It holds historical data from many systems in one agreed format so it can be compared. The difference from an ordinary store database is that the store database has to handle an order quickly, while the warehouse has to answer a question about a thousand orders quickly. It is also a tool for running the business on data rather than on impressions from ad platforms. ** ### Why platform totals do not add up to revenue Each ad platform attributes sales to itself according to its own model and its own time window, so the same transaction can be counted two or three times. It is not a system error but a result of none of them knowing about the others. Resolving such conflicts is one of the main reasons for building a warehouse. ** ### Contribution margin as the decision metric Revenue minus product cost, returns, shipping and payment costs, and ad cost gives a number you can move budget on. Platform ROAS cannot replace it, because of those costs it only knows the ad cost. Agreeing this definition is the first step of implementation and usually the most contentious, because it touches accounting. ** ### An ecommerce data warehouse and one for a service business A store has an order with a price and a cost, so the account closes inside the warehouse. A service business has an enquiry whose value appears only after a sales conversation, so the warehouse has to reach into the CRM, and some figures stay estimates until the contract is signed. That changes the scope of the project and we price it differently. ** ### Data warehouse from Kraków, done remotely Our office is in Kraków, and the project is remote by nature, because the work happens in the cloud and in the client's systems, so we deliver it for companies across Poland and abroad. It is worth meeting live once, when agreeing the definition of an order and of margin, because marketing, sales and accounting all need to be at that table at the same time. ** ### How data gets into the warehouse: ETL A data warehouse gathers data from different sources in one consistent format. The ETL process pulls it from operational systems such as the store, the ERP and the warehouse management system, then it has to be processed and structured, and finally it lands in an analytical database. That way integrated data from ads, stock levels and orders can be analysed together instead of being kept in separate spreadsheets. Real-time refreshing is rarely needed: for budget decisions a daily rhythm is enough, and that makes it possible to optimise query cost and performance with large volumes of data. Other services ## What else can we do for you? A data warehouse rarely works in isolation: the data first has to be measured correctly, and then campaigns are run on those numbers. Below are the pages that most often come into the same conversation, each with its own scope and its own quote. [### Web analytics Web analytics for online stores and websites: GA4, Tag Manager, consent and server-side tracking. View ›](https://justidea.agency/en/services/marketing-agency/web-analytics/) [### Server-side GTM We implement server-side Google Tag Manager (server-side tagging): tagging on the server that is resistant to blockers and cookie limits. View ›](https://justidea.agency/en/services/marketing-agency/server-side-tagging/) [### Google Ads advertising A Google Ads agency that asks about margin, returns and shipping cost before deciding on the budget. View ›](https://justidea.agency/en/services/marketing-agency/google-ads/) ## Let us start by checking whether your data can be joined at all The source audit shows what you have, at what quality and what is missing to calculate profit per channel. It ends with a data map and a cost estimate, not a presentation. ![The audit checks the quality of data from ads, the store and the warehouse, and ends with a data map and a cost estimate](https://justidea.agency/assets/ill-hurtownia-danych-profit-analytics-audyt.svg) Book a call about your store's margin A free, no-obligation 30-minute call Book a call about your store's margin Contact ## A conversation about your numbers: 30 minutes The call is led by a new business specialist. When we get into the details of an account, the specialist for that channel joins in. We reply within one business day. A quick review of your tracking and campaignsThree priorities for the next quarterA written summary that stays with you Before the meeting we review your website, your visibility and what your campaigns show from the outside. We will not open with “so, what does your company do?”. [4.96 224 reviews](https://justidea.agency/en/justidea-reviews/) What happens after you send it 01 within 1 business day ### We reply to your email The reply comes from the same new business specialist who will run the call. No qualification form and no call from an unknown number. 02 this week ### A 30-minute conversation We go through your numbers and your questions. If it turns out we are not the right fit, we will tell you straight away.