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tmssoftware/datamodeler

23PascalAudience · developerComplexity · 3/5ActiveLicenseSetup · moderate

TLDR

Windows desktop tool for designing database schemas as ER diagrams and generating DDL scripts for SQL Server, Firebird, Oracle, PostgreSQL, MySQL, and SQLite.

Mindmap

mindmap
  root((datamodeler))
    Inputs
      ER diagram
      Existing database
      Project versions
    Outputs
      DDL scripts
      Alter scripts
      Delphi Aurelius classes
    Use Cases
      Schema design
      Reverse engineer DB
      Cross-DB conversion
      Model versioning
    Tech Stack
      Delphi
      Pascal
      Windows
      TMS libraries

Things people build with this

USE CASE 1

Design a new database schema visually and generate DDL for your target SQL engine

USE CASE 2

Reverse engineer an existing database into an editable ER diagram

USE CASE 3

Generate alter scripts that migrate a deployed database to a new model version

USE CASE 4

Convert a schema between database systems like Oracle and PostgreSQL

Tech stack

DelphiPascalWindowsTMS AureliusVCL

Getting it running

Difficulty · moderate Time to first run · 30min

Windows-only installer, and database client libraries for each target DB must be installed separately.

Source available, free for personal, educational, evaluation, and open source use, but commercial use requires a paid license.

In plain English

TMS Data Modeler is a Windows desktop tool for designing the structure of databases through visual diagrams. You draw the tables and the relationships between them, and the tool can then generate SQL scripts that build that database on your server of choice. The README lists support for SQL Server, Firebird, Oracle, PostgreSQL, MySQL, and SQLite. The tool is written in Delphi and the source code in this repository is written in Pascal. The main use cases are creating a new schema as an entity relationship diagram, generating DDL scripts to build the database on a target system, generating alter scripts that move an existing database between model versions, reverse engineering an existing database into a diagram, comparing project versions, validating a model for errors, and converting between database systems. The diagram editor supports tables, fields, domains, indexes, triggers, relationships, constraints, views, procedures, generators, and logical application level domains. There is also a feature called database first integration for TMS Aurelius, which generates entity mapped Delphi classes from the same model. The project is delivered as Windows installers from the Releases page of the repository. It runs on Windows 10 or later. The README notes that the database client libraries for whichever systems you want to connect to are not bundled, so you install them separately. There is no separate trial build, and the license terms allow free use for personal learning, education, evaluation, and open source projects, but commercial use requires a paid license. If you want to build the source yourself you need Delphi 13, since earlier Delphi versions are untested. The third party libraries are listed in a snapshot file at the repo root and include JAM Software Virtual TreeView, TMS Aurelius, TMS Scripter, TMS Diagram Studio, and the TMS VCL UI Pack. The recommended path is to run tms restore tms snapshot yaml with the skip register flag from the repository root, which uses TMS Smart Setup to pull every dependency and produce the final dm exe. A manual path is also documented: install each dependency yourself, open dm slash dm dproj in Delphi 13, and build. The license is described as source available rather than open source. Pull requests are accepted, but contributors agree that TMS Software gets the rights it needs to ship the contribution. Support runs through the TMS Support Center, and release notes live on the TMS documentation site.

Copy-paste prompts

Prompt 1
Walk me through installing TMS Data Modeler on Windows and connecting it to PostgreSQL
Prompt 2
Show how to reverse engineer a MySQL database into a Data Modeler diagram
Prompt 3
Generate an alter script from one project version to another and explain its sections
Prompt 4
Build the dm.exe from source using TMS Smart Setup and tms snapshot yaml in Delphi 13
Prompt 5
Use Database First integration to produce TMS Aurelius mapped Delphi classes from a schema
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Generated 2026-05-22 · Model: sonnet-4-6 · Verify against the repo before relying on details.