ERP Integration with a B2B Portal — How It Actually Works

Why ERP Integration Makes or Breaks a B2B Portal

A B2B portal without ERP integration is just a fancy order form. Your team still has to manually enter orders into the system, update stock levels by hand, and maintain two separate product databases. That defeats the entire purpose.

The integration between your ERP and your B2B portal is what transforms online ordering from "another thing to manage" into an actual time-saver. When done right, data flows automatically in both directions: product information and stock levels go from the ERP to the portal, and orders flow from the portal back to the ERP.

This article explains how that integration works in practice — the technical approaches, the data that needs to move, the timeline, and the things that commonly go wrong.

Three Integration Approaches

1. API Integration (Recommended)

The ERP exposes an API (Application Programming Interface) — a structured way for external systems to read and write data. The B2B portal calls the API to fetch products, prices, and stock levels, and pushes orders back through the same API.

Best for: Modern ERPs with REST or SOAP APIs (enova365, SAP Business One, Microsoft Dynamics, Comarch ERP XL)

Timeline: 3–5 days

Pros: Real-time data, reliable, bidirectional

2. File-Based Sync

The ERP exports data as files (CSV, XML, or JSON) to a shared location (FTP server, network folder, cloud storage). The portal picks up these files on a schedule, processes them, and drops order files back for the ERP to import.

Best for: Older ERPs without APIs, or systems where API access is restricted (Subiekt GT, some Optima configurations)

Timeline: 7–10 days

Pros: Works with virtually any ERP, low technical requirements on the ERP side

Cons: Not real-time (typically 15–60 minute sync intervals), more failure points

3. Direct Database Connection

The portal reads directly from the ERP's database and writes orders to designated tables. This is technically the fastest approach but carries significant risk — a bug in the portal could corrupt ERP data.

Best for: Almost never recommended. Only considered when no other option exists.

What Data Flows Between Systems

Data	Direction	Frequency	Notes
Products (name, SKU, description)	ERP → Portal	Daily or on change	Full catalog sync
Prices (per client/group)	ERP → Portal	Every 15–60 min	Must reflect current price lists
Stock levels	ERP → Portal	Every 5–15 min	Critical for order accuracy
Product images	Manual or ERP → Portal	On change	Often managed separately
Orders	Portal → ERP	Real-time	Each order becomes a sales document
Order status	ERP → Portal	Every 15–60 min	Confirmed, shipped, invoiced
Invoices (PDF)	ERP → Portal	On generation	Clients download from portal
Client data	ERP → Portal	Daily	New accounts, updated terms

Common Polish ERPs and Integration Realities

Subiekt GT (InsERT)

The most popular ERP among small and medium Polish businesses. Subiekt GT does not have a native REST API, but it supports:

• Sfera — InsERT's SDK for external integrations. Allows reading and writing data programmatically. Requires a Windows machine running the Sfera service.
• Direct database access — Subiekt uses a Firebird database. It is possible to read data directly, but writing should go through Sfera to maintain data integrity.
• File export — Subiekt can export product lists, price lists, and stock reports to CSV.

Typical integration approach: Sfera for orders (write), direct DB read + file export for products/prices/stock. Timeline: 5–7 days.

Comarch Optima

Optima offers an API through Comarch's integration platform, but its availability and quality depend on the module and version. Common approach:

• Optima API — available for newer versions, covers products, contractors, and documents
• File exchange — Optima supports XML import/export for most document types
• Direct SQL — Optima uses MS SQL Server; read access is straightforward

Typical integration approach: API where available, file exchange as fallback. Timeline: 5–8 days.

enova365

The most integration-friendly Polish ERP. enova365 has a well-documented REST API that covers products, prices, stock, orders, invoices, and contractors. Most B2B portal integrations with enova365 are pure API.

Timeline: 3–5 days.

SAP Business One

SAP B1 offers the Service Layer (REST API) and DI API. Both are well-documented. Integration is straightforward but SAP's data model is complex, so mapping takes longer.

Timeline: 5–7 days.

What Can Go Wrong (And How to Avoid It)

1. Price mismatches — The portal shows one price, the ERP has another. Usually caused by sync delays or different rounding rules. Fix: Sync prices every 15 minutes minimum, and validate prices at order confirmation against the ERP.

2. Stock overselling — Two clients order the last 10 units simultaneously. Fix: Reserve stock at order placement, not confirmation. Implement a stock buffer (show 95% of actual stock).

3. Product codes diverge — The ERP uses one SKU format, the portal another. Fix: Use the ERP's product code as the single source of truth. Never create a parallel coding system.

4. Sync failures go unnoticed — The file export breaks, and nobody notices for 3 days. Fix: Automated monitoring with alerts. If sync has not run in the expected interval, someone gets notified.

5. Character encoding issues — Polish characters (ą, ę, ś, ź) get mangled in file transfers. Fix: Enforce UTF-8 everywhere. Test with Polish product names before go-live.

Learn more about our B2B portal solutions and how we handle ERP integration. Not sure which portal option fits your business? See the platform comparison to evaluate SaaS vs. custom portal options.

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