* data validation
* data serialization
* data documentation, etc.

This works the same way as with Pydantic models. And it is actually achieved in the same way underneath, using Pydantic.

/// info

Keep in mind that dataclasses can't do everything Pydantic models can do.

So, you might still need to use Pydantic models.

Does nothing. false true false false false true generate-sources org.apache.maven.plugin.coreit.CMojo java per-lookup once-per-session models java.lang.String[] false true version java.lang.String false true ${version} xpp3-writer Does nothing. false true false false false true generate-sources org.apache.maven.plugin.coreit.BMojo java per-lookup once-per-session models java.lang.String[] false true version java.lang.String false true ${version} org.apache.maven maven-plugin-api jar 2.0 org/apache/m...

        <groupId>org.codehaus.modello</groupId>
        <artifactId>modello-maven-plugin</artifactId>
        <configuration>
          <version>1.2.0</version>
          <models>
            <model>../../api/maven-api-metadata/src/main/mdo/metadata.mdo</model>
          </models>
          <params>
            <param>forcedIOModelVersion=1.1.0</param>
            <param>packageModelV3=org.apache.maven.artifact.repository.metadata</param>

    boolean isResolveDependencies();

    /**
     * Controls the level of validation to perform on processed models. By default, models are validated in strict mode.
     *
     * @param validationLevel The level of validation to perform on processed models, e.g.
     *            {@link org.apache.maven.model.building.ModelBuildingRequest#VALIDATION_LEVEL_STRICT}.

To distinguish from the models with all optional values for **updates** and models with required values for **creation**, you can use the ideas described in [Extra Models](extra-models.md){.internal-link target=_blank}.

import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.di.Named;
import org.apache.maven.api.model.Model;

/**
 * Interface for model transformers that can modify Maven project models at different stages of processing.
 * <p>
 * Model transformers allow plugins and extensions to modify the POM model during the build process.
 * Transformations can be applied at three different stages:
 * <ol>

You can see those schemas because they were declared with the models in the app.

That information is available in the app's **OpenAPI schema**, and then shown in the API docs.

That same information from the models that is included in OpenAPI is what can be used to **generate the client code**.

### Hey API { #hey-api }

        <artifactId>modello-maven-plugin</artifactId>
        <version>1.0.1</version>
        <configuration>
          <version>1.1.0</version>
          <models>
            <model>src/main/mdo/remote-resources.mdo</model>
          </models>
        </configuration>
      </plugin>
    </plugins>
  </build>

To declare a **request** body, you use <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> models with all their power and benefits.

/// info

To send data, you should use one of: `POST` (the more common), `PUT`, `DELETE` or `PATCH`.

We'll fix these things by adding a few **extra models**. Here's where SQLModel will shine. ✨

### Create Multiple Models { #create-multiple-models }

In **SQLModel**, any model class that has `table=True` is a **table model**.

And any model class that doesn't have `table=True` is a **data model**, these ones are actually just Pydantic models (with a couple of small extra features). 🤓