---
title: Phi-3 Mini SQL Generator
emoji: 🧠
colorFrom: yellow
colorTo: purple
sdk: gradio
sdk_version: 6.5.1
app_file: app.py
pinned: false
license: apache-2.0
short_description: "SQL generator powered by Phi-3 Mini fine-tuning"
---

# Phi-3 Mini SQL Generator

A text-to-SQL app built around a QLoRA fine-tuned Phi-3 Mini model for converting natural-language questions to SQL queries.

## What the App Does

The app accepts a table schema plus a natural-language SQL question. It uses deterministic code for schema creation/editing and high-confidence guardrail templates, then calls the fine-tuned model only for supported text-to-SQL generation.

The base model is not live-loaded in the Space. It is kept as offline evaluation evidence so the CPU demo does not pretend to run two 3.8B models interactively.

## Model-Generated vs Deterministic

| Behavior | Source |
| --- | --- |
| Non-template `SQL_QUERY` after schema selection | Fine-tuned Phi-3 Mini |
| High-confidence ranking/count/aggregation queries | Deterministic SQL template |
| `CREATE_TABLE` from explicit user columns | Deterministic schema parser |
| `EDIT_TABLE` add/remove/rename columns | Deterministic schema parser |
| Greetings, off-topic requests, unknown intents | Static fallback |

Boundary rule: deterministic SQL, schema parsers, translations, and fallbacks are not model capability. They are product guardrails around the model.

## Training and Evaluation Story

- **Base model:** [`microsoft/Phi-3-mini-4k-instruct`](https://huggingface.co/microsoft/Phi-3-mini-4k-instruct)
- **Dataset:** `b-mc2/sql-create-context`, sampled to 1,000 training examples.
- **Training method:** QLoRA adapter fine-tuning, then merged for simpler CPU inference.
- **Published merged model:** [`Shizu0n/phi3-mini-sql-generator-merged`](https://huggingface.co/Shizu0n/phi3-mini-sql-generator-merged)
- **Primary metric:** exact match on held-out text-to-SQL examples.

| Model | Exact match |
| --- | ---: |
| Base Phi-3 Mini | 2.0% |
| Fine-tuned QLoRA merged | 73.5% |

Reported gain: **+71.5 percentage points** over the base model.

Known limits:

- The training data is mostly `SELECT`; `INSERT`, `UPDATE`, and `DELETE` are not a reliable model capability.
- Unsupported DML requests are not generated by the model and must not be disguised as schema edits. For example, `delete species` can remove a schema column, but `delete all animals` returns a static unsupported-scope fallback.
- PT-BR input is not trained model capability. The app handles selected PT-BR cases through deterministic normalization/templates.
- Conversational chat and JSON schema proposal are out of scope and use fallback behavior instead of model prompts.
- Exact match does not prove semantic perfection. It is useful evidence, not a substitute for qualitative review.

## AI Engineering Story

The product layer exists because a fine-tuned model is not the same thing as a reliable app.

- Intent routing limits the model path to `SQL_QUERY`.
- Deterministic schema tools handle explicit create/edit requests without loading the model.
- High-confidence SQL templates handle simple ranking, aggregation, count, and comparison queries before the CPU model path.
- SQL output is validated with `sqlparse`; model output is also checked against the active `CREATE TABLE` schema before it can be shown as accepted model SQL.
- Lazy loading keeps startup cheap; the model is downloaded and loaded only when needed.
- Load and generation timeouts protect the UI from indefinite waits.
- Static fallbacks make unsupported behavior visible instead of laundering it as AI.
- Every user-visible response/status/error with a known source must preserve provenance: fine-tuned model, deterministic SQL template, deterministic schema parser, or static fallback.

## How to Use

1. Click **Load fine-tuned model**.
   - Loading is lazy: the model is only downloaded and loaded when you request it.
   - On CPU, the first load can take a few minutes.
2. Select, create, or edit the **SQL table schema**.
   - You can use the presets: `employees`, `orders`, `students`, `products`, `sales`.
   - You can also ask for explicit schema operations, such as `create table products with id name price` or `add stock`.
3. Enter the question in the chat input.
4. Click **Send**.
5. Review the result in `gr.Code(language="sql")` and the source/status message.
   - The app shows a validation badge powered by `sqlparse` plus active-schema checks for model output.
   - Known-source errors should still identify their source path; unknown-source errors should not fake certainty.

## Usage Examples

Use this path to show both sides of the project without muddying provenance.

1. **Model path:** load the fine-tuned model, select `employees`, and ask `show employees in Engineering ordered by salary`.
2. **Template path:** ask `qual o produto mais caro?` with the `products` schema — returns deterministic SQL.
3. **Schema parser:** ask `create table animals with id name species weight`, then `add habitat` — deterministic schema manipulation.
4. **Fallback:** ask `what can you do?` — static response since chat is outside model training.
5. **Evaluation:** point to the base-vs-fine-tuned exact-match numbers.

## Models

- Fine-tuned adapter: [Shizu0n/phi3-mini-sql-generator](https://huggingface.co/Shizu0n/phi3-mini-sql-generator)
- Fine-tuned merged model used in the app: [Shizu0n/phi3-mini-sql-generator-merged](https://huggingface.co/Shizu0n/phi3-mini-sql-generator-merged)
- Offline baseline model used for evaluation: [microsoft/Phi-3-mini-4k-instruct](https://huggingface.co/microsoft/Phi-3-mini-4k-instruct)

## Current Features

- Gradio UI with a step-by-step flow: load the fine-tuned model, define schema context, and inspect SQL artifacts.
- Intent routing with 5 supported routes: `CREATE_TABLE`, `EDIT_TABLE`, `SQL_QUERY`, `SMALLTALK`, `UNKNOWN`.
- Model calls only for non-template `SQL_QUERY`; deterministic templates may answer supported SQL shapes before model load.
- Smalltalk and unknown messages use a static fallback.
- Lazy loading to reduce startup cost.
- Preserved Phi-3 patches for local/Spaces compatibility.
- Schema presets without blocking manual input.
- SQL output separated from errors/status so booleans, integers, and error messages do not appear inside the SQL block.
- Centered loading overlay to make the loading state obvious.

## Model Probe

The normal pytest suite does not load the 3.8B model. To manually verify the real model behavior:

```bash
python scripts/model_probe.py
```

The probe prints JSON with pass/fail checks for static fallback, deterministic CREATE TABLE, deterministic schema edit, SQL query generation, and smalltalk while a schema is active.

## Tests

```bash
set PYTHONPATH=. && pytest tests/test_chatbot_core.py tests/test_chatbot_behavior.py -q
```

Current unit suite: **141 tests**. These tests avoid loading the 3.8B model and focus on routing, deterministic tools, prompt construction, model-output rejection, active-schema validation, SQL validation, UI schema-context synchronization, and error handling.

## Run Locally

```bash
python -m pip install -r requirements.txt
python app.py
```

Then open the address shown by Gradio, usually `http://127.0.0.1:7860`.