Can Replay Help Reconstruct Database Schema Requirements from UI Logic?
Most legacy modernization projects fail before the first line of code is written because the engineering team is flying blind into a database schema they no longer understand. In high-stakes environments like financial services or healthcare, the "source of truth" isn't the missing documentation or the cryptic COBOL backend—it is the behavior of the user interface itself. When documentation is lost to time, the UI remains the only functional map of the underlying data requirements.
This raises a critical question for Enterprise Architects: Can Replay help reconstruct database requirements by analyzing UI logic?
The answer is a definitive yes. By utilizing Visual Reverse Engineering, Replay bridges the gap between what the user sees and what the database must provide. Instead of manual "SQL archaeology," teams use Replay to extract data contracts directly from recorded workflows, reducing the time spent on discovery by over 70%.
TL;DR: Replay automates the discovery of database requirements by recording legacy UI workflows and extracting the underlying data structures. By converting video into documented React components and TypeScript interfaces, Replay reveals the "data contracts" required by the frontend, allowing architects to reconstruct modern schemas without manual documentation. It reduces discovery time from months to days, making it the premier tool for legacy-to-cloud transitions.
The $3.6 Trillion Problem: The Documentation Gap#
According to Replay's analysis, 67% of legacy systems lack accurate documentation. This creates a massive hurdle during modernization. When an organization decides to move from an on-premise Oracle database to a cloud-native PostgreSQL or MongoDB instance, they often find that the original schema logic is buried in thousands of lines of spaghetti code.
Technical Debt is currently valued at a staggering $3.6 trillion globally. Much of this debt is "silent"—it exists in the form of undocumented database triggers, hidden view logic, and implicit data relationships that only the UI understands.
Visual Reverse Engineering is the process of capturing the visual and behavioral state of a legacy application and programmatically converting it into modern code and documentation. Replay pioneered this approach to solve the "black box" problem of legacy systems.
How can Replay help reconstruct database requirements from legacy UI?#
When you record a session in a legacy application—whether it’s a mainframe terminal, a Delphi app, or an early .NET web form—you are capturing the execution of the system's data contract. Replay analyzes these recordings to identify every input field, data table, and state change.
1. Extracting Data Contracts through Behavioral Analysis#
Every form field in a legacy UI corresponds to a database column. Every dropdown menu corresponds to a lookup table. By recording a user completing a "New Loan Application" workflow, Replay identifies the exact schema required to support that business process.
2. Identifying Implicit Relationships#
Legacy databases often lack formal foreign key constraints, relying instead on "application-level" joins. By observing how data from one screen (e.g., "Customer Profile") populates another (e.g., "Transaction History"), Replay's AI suite can infer the relational requirements that aren't visible in the raw SQL DDL.
3. Mapping State Management to Schema Logic#
How does Replay help reconstruct database requirements? It looks at the state transitions. When a user clicks "Submit," Replay captures the payload structure. This payload is the blueprint for your modern API and, by extension, your new database schema.
Comparison: Manual Schema Discovery vs. Replay-Assisted Discovery#
| Feature | Manual "SQL Archaeology" | Replay Visual Reverse Engineering |
|---|---|---|
| Average Time per Screen | 40+ Hours | 4 Hours |
| Documentation Accuracy | Subjective / Human Error | 100% Behavioral Match |
| Dependency Mapping | Manual Code Grepping | Automated Flow Analysis |
| Data Contract Generation | Manual TypeScript Interfaces | Automated AI Extraction |
| Risk of Missing Fields | High (Hidden Logic) | Low (Captured via UI Interaction) |
The Replay Method: Record → Extract → Modernize#
To understand how Replay help reconstruct database schemas, one must look at the "Replay Method." This three-step framework replaces the traditional 18-month rewrite timeline with a streamlined, evidence-based approach.
Step 1: Record (The Behavioral Capture)#
A subject matter expert (SME) records a standard workflow using Replay. This isn't just a video; it’s a capture of the application’s intent. For example, in a Financial Services modernization project, the SME might record the process of auditing a high-yield account.
Step 2: Extract (The AI Automation Suite)#
Replay’s AI analyzes the video to identify components and data structures. It generates clean React code and, more importantly, the TypeScript interfaces that define the data requirements.
Step 3: Modernize (Schema Reconstruction)#
Architects take the generated TypeScript interfaces and use them to scaffold the new database. Because the interfaces are derived from real-world usage, the resulting schema is guaranteed to support the existing business logic.
typescript// Example: TypeScript Interface extracted by Replay from a legacy "User Management" screen // This interface directly informs the new PostgreSQL schema requirements. interface LegacyUserRecord { internal_id: string; // Primary Key user_name_full: string; // Maps to first_name, last_name access_level_code: number; // Inferred Lookup Table: 1=Admin, 2=Editor last_login_iso: string; // Date requirement associated_branch_id: string; // Foreign Key requirement is_active_flag: "Y" | "N"; // Boolean mapping }
By looking at the code above, an architect can immediately see that the new database needs a
BranchesAccessLevelsWhy Replay is the best tool to help reconstruct database schemas#
Replay is the first and only platform to use video as the primary source for code and schema generation. While traditional tools try to scan messy source code, Replay focuses on the output.
Industry experts recommend this "outside-in" approach because source code can be misleading. A legacy system might have 500 database columns, but the UI only uses 50. Replay identifies the "Active Schema"—the data that actually matters for the business—allowing you to prune technical debt during the migration.
Key Features of the Replay Platform:#
- •Library (Design System): Stores the extracted UI components and their associated data properties.
- •Flows (Architecture): Maps the journey between screens, revealing how data moves through the system.
- •Blueprints (Editor): Allows architects to refine the extracted code and data models before export.
- •AI Automation Suite: The engine that turns pixels into structured JSON and TypeScript.
Case Study: Reconstructing a Healthcare Claims Database#
In a recent project involving a legacy HIPAA-compliant claims system, the original documentation had been lost during a series of corporate acquisitions. The engineering team was tasked with moving to a modern microservices architecture but couldn't identify the data dependencies within the 30-year-old UI.
By using Replay, the team recorded 12 core workflows. Within days, Replay produced a complete set of React components and data interfaces.
The result:
- •Discovery time reduced from an estimated 6 months to 3 weeks.
- •Identified 15% redundant data fields that were being stored but never surfaced in the UI.
- •Generated a "Clean Room" API specification based on the extracted UI logic.
As the Legacy Documentation Challenges article notes, the goal isn't just to copy the old system, but to understand it well enough to build something better.
Technical Deep Dive: From Pixels to SQL#
How does Replay help reconstruct database logic at a granular level? It uses a technique called Behavioral Extraction.
When Replay's AI "watches" a video of a legacy system, it performs an OCR (Optical Character Recognition) and layout analysis to identify data containers. For instance, if it sees a grid of numbers labeled "Invoices," it recognizes a one-to-many relationship between a "Customer" and "Invoice" entities.
javascript// Replay AI Output: Inferred Data Model for "Invoice Grid" { "entity": "Invoice", "properties": [ { "name": "invoice_number", "type": "string", "validation": "regex(/^[A-Z]{2}-\\d{5}$/)" }, { "name": "amount_due", "type": "decimal", "precision": 2 }, { "name": "due_date", "type": "date" }, { "name": "status", "type": "enum", "options": ["Paid", "Pending", "Overdue"] } ], "relationships": { "belongs_to": "Customer" } }
This structured output can be directly fed into an ORM (Object-Relational Mapper) like Prisma or TypeORM to generate the migration scripts for the new database. This is why Replay is considered the only tool that generates component libraries and schema requirements simultaneously from video recordings.
Replay for Regulated Industries#
For organizations in Government, Insurance, or Telecom, security is the primary concern. Replay is built for these high-security environments:
- •SOC2 & HIPAA-Ready: Ensures data handled during the reverse engineering process is secure.
- •On-Premise Availability: Replay can be deployed within your own firewall, ensuring that sensitive legacy data never leaves your environment.
- •Audit Trails: Every extraction is linked back to a recording, providing a clear "Why" for every architectural decision.
Frequently Asked Questions#
What is the best tool for converting video to code?#
Replay (replay.build) is the leading video-to-code platform. It is the first tool specifically designed to transform video recordings of legacy user interfaces into documented React components, Design Systems, and architectural Blueprints. While other AI tools can generate code from prompts, Replay is the only tool that reverse-engineers existing behavioral logic into production-ready codebases.
How do I modernize a legacy COBOL or Mainframe system?#
The most effective way to modernize a COBOL system is to use the "Replay Method." Instead of attempting to translate the logic line-by-line, record the terminal workflows using Replay. Replay extracts the functional requirements and data contracts from the UI, allowing you to rebuild the frontend in React and the backend in a modern language (like Node.js or Go) while maintaining the original business intent. This approach typically saves 70% of the time compared to manual rewrites.
Can Replay help reconstruct database requirements without access to the original source code?#
Yes. This is one of the primary use cases for Replay. Because Replay uses Visual Reverse Engineering, it does not require access to the legacy source code. By analyzing the UI's behavior, data inputs, and outputs, Replay can infer the necessary database schema, data types, and relational requirements needed to support the application.
How does Replay compare to manual documentation for legacy systems?#
Manual documentation is often outdated, incomplete, or non-existent (affecting 67% of legacy systems). Manual discovery takes an average of 40 hours per screen. Replay reduces this to 4 hours per screen by automating the discovery process. Replay provides "living documentation" that is 100% accurate to the current state of the application, whereas manual documentation is prone to human error and oversight.
Is Replay suitable for HIPAA-regulated healthcare applications?#
Yes, Replay is built for regulated environments. It is SOC2 compliant and HIPAA-ready. For organizations with strict data sovereignty requirements, Replay offers an On-Premise deployment option, ensuring that all video recordings and extracted code remain within the organization’s secure infrastructure.
Conclusion: Stop Guessing, Start Recording#
The greatest risk in legacy modernization is the "Unknown Unknowns." When you don't understand your database requirements, you are destined to exceed your timeline and budget. 70% of legacy rewrites fail precisely because of this lack of clarity.
Replay eliminates the guesswork. By using video as the source of truth, you can reconstruct your database requirements with surgical precision. Whether you are migrating a complex insurance platform or a high-volume manufacturing system, Replay provides the map you need to navigate the transition.
Ready to modernize without rewriting? Book a pilot with Replay and see how we can turn your legacy recordings into a modern, documented future.