remodel-core

remodel-core is a Rust library for database modeling. It lets you build conceptual ER models, convert them into logical relational schemas, and render SQL DDL for supported dialects.

This crate is a Rust reimplementation of the core modeling engine from brModelo by Carlos Henrique Candido and contributors. The port keeps the same GPL-3.0-or-later licensing model.

What it provides

Conceptual modeling primitives: entities, attributes, relationships, cardinalities, specializations, unions, and associative entities.
Logical modeling primitives: tables, columns, primary keys, unique constraints, and foreign keys.
Conceptual-to-logical transformation with configurable strategies for relationships, specializations, and complex attributes.
SQL DDL rendering for PostgreSQL, MySQL, and SQLite.
Validation diagnostics for structurally invalid diagrams.
serde support for persistence and interchange formats.

Installation

cargo add remodel-core

Quick start

use remodel_core::models::conceptual::AttributeOwner;
use remodel_core::prelude::*;

fn main() -> Result<()> {
    let mut model = ConceptualModel::new("library");

    let book = model.add_entity("Book");
    model.add_primary_attribute(book, "id", DataType::Integer)?;
    model.add_attribute(
        AttributeOwner::Entity(book),
        "title",
        DataType::Varchar(255),
    )?;

    let author = model.add_entity("Author");
    model.add_primary_attribute(author, "id", DataType::Integer)?;
    model.add_attribute(
        AttributeOwner::Entity(author),
        "name",
        DataType::Varchar(120),
    )?;

    model
        .relate("wrote", book, Cardinality::ZeroToMany)
        .with(author, Cardinality::OneToMany)
        .id();

    let logical = model.to_logical()?;
    let sql = logical.to_sql(SqlDialect::Postgres);

    println!("{sql}");
    Ok(())
}

This produces a relational model with Book, Author, and a junction table for wrote.

Modeling pipeline

remodel-core follows the usual database-design flow:

Build a conceptual model.
Validate and convert it into a logical model.
Render SQL DDL for the target database dialect.

The main APIs are:

ConceptualModel for ER authoring
ConceptualModel::to_logical() for default conversion
transform::conceptual_to_logical() when you need custom ConvertOptions
LogicalModel::to_sql() for final DDL generation

Supported SQL dialects

PostgreSQL
MySQL / MariaDB
SQLite

Validation

The library validates conceptual models before conversion. Structural problems such as missing references or invalid identifiers are reported through diagnostics, and conversion returns Error::Validation when errors are present.

Release

Publishing to crates.io is automated through GitHub Actions:

Push a tag named remodel-core-vX.Y.Z, or
Run the Publish remodel-core workflow manually.

The workflow runs the crate tests and then publishes RemodelCore/ using the repository secret CARGO_REGISTRY_TOKEN.

License

GPL-3.0-or-later.

remodel-core 0.1.0