🐷 piglets

A modular library of text-to-SQL tools.

Status

piglets is currently an alpha-stage package. The API is expected to evolve before 1.0.

Get started

Install

venv

pip install piglets

uv

uv add piglets

Install the optional dependency for the model provider you use. For OpenAI:

venv

pip install "piglets[openai]"

uv

uv add "piglets[openai]"

Other provider extras include anthropic, google_genai, google_vertexai, bedrock, cohere, mistralai, groq, ollama, and openrouter.

Install the optional dependency for the database backend you use. For BigQuery:

venv

pip install "piglets[bigquery]"

uv

uv add "piglets[bigquery]"

Logical planning

Use gpt-5.2 to generate 3 logical plans from a natural language query.

from piglets import LogicalPlanner

# initialise a logical planner
logical_planner = LogicalPlanner('gpt-5.2')

# generate 3 logical plan samples and aggregate them
logical_plan = logical_planner.plan(
    natural_language_query="What was the average number of piglets per week for Q4 2025?",
    num_samples=3,
)

# print the aggregated logical plan
for i, step in enumerate(logical_plan.logical_steps):
    print(f"Step {i + 1}: ")
    print(step)

# inspect the candidate plans used to create the aggregate
print(f"Aggregated from {len(logical_plan.sample_plans)} sample plans.")

>>> Step 1:
>>> 1. Identify all piglet birth (or piglet addition) events with their event dates and piglet counts.
>>> Step 2:
>>> 2. Filter the events to the Q4 2025 date range (Oct 1, 2025 through Dec 31, 2025).
>>> Step 3:
>>> 3. Assign each event to a calendar week within that quarter using a consistent week definition (e.g., week starting Monday or Sunday).
>>> Aggregated from 3 sample plans.
...

Database connector

Use DatabaseConnector to inspect a database and return a typed schema. Pass either a SQLAlchemy URL, a connection string, or one of Piglets' helper URL classes.

from piglets import BigQueryURL, DatabaseConnector

database_connector = DatabaseConnector(
    connection=BigQueryURL(
        dataset="my_bigquery_dataset",
    ),
)

database = database_connector.get_database_schema()

print(database.name)
for table in database.tables:
    print(table.name)
    for column in table.columns:
        print(f"- {column.name} ({column.data_type})")

BigQuery connections can include an explicit GCP project ID:

database_connector = DatabaseConnector(
    connection=BigQueryURL(
        project_id="my-gcp-project",
        dataset="my_bigquery_dataset",
    ),
)

Supported databases

DatabaseConnector supports any database URL accepted by SQLAlchemy. Use URL for SQLAlchemy-native dialects and Piglets helper URL classes where the connection string has backend-specific parameters.

For a SQLAlchemy-native database, create a standard SQLAlchemy URL:

from piglets import DatabaseConnector, URL

database_connector = DatabaseConnector(
    connection=URL.create(
        drivername="sqlite",
        database="example.db",
    ),
)
database = database_connector.get_database_schema()

For a backend with a Piglets helper class, pass that URL object directly:

from piglets import DatabaseConnector, SnowflakeURL

database_connector = DatabaseConnector(
    connection=SnowflakeURL(
        account="my-account",
        user="my-user",
        password="my-password",
        database="SNOWFLAKE_SAMPLE_DATA",
        schema="TPCH_SF1",
    ),
)
database = database_connector.get_database_schema()

Dual-pathway pruning

Use Pruner to reduce a database schema with both preservation and deletion signals. The preservation pathway selects tables and columns that look useful for the query. The deletion pathway removes tables and columns that look irrelevant. dual_pathway_pruning() combines both paths into a final Database schema.

from piglets import BigQueryURL, DatabaseConnector, LogicalPlanner, Pruner

question = "Which tags saw the largest increase in average answer score from 2022 to 2023, considering only questions with at least 5 answers?"

logical_planner = LogicalPlanner("gpt-5.2")
logical_plan = logical_planner.plan(
    natural_language_query=question,
    num_samples=3,
)

database_connector = DatabaseConnector(
    connection=BigQueryURL(
        dataset="stack_overflow",
    ),
)
database = database_connector.get_database_schema()

pruner = Pruner(model_name="gpt-5.2")
pruned_database = pruner.dual_pathway_pruning(
    natural_language_query=question,
    database=database,
    logical_plan=logical_plan,
)

print(pruned_database.export_as_string())

Semantic Linking

You can use SemanticLinker to combine a Database and a LogicalPlan into schema-specific instructions.

from piglets import SemanticLinker

semantic_linker = SemanticLinker(model_name=MODEL_NAME)

semantic_linking_result = semantic_linker.link(
    natural_language_query=QUESTION,
    database=database,
    logical_plan=logical_plan,
)

Here database is a Database and logical_plan is a LogicalPlan or AggregatePlan.

The semantic_linking_result is of type SemanticLinkingResult and includes the following fields:

• database_structure: Overview of the database structure relevant to the user query.
• query_specific_content_analysis: Detailed analysis mapping the query intent to tables, columns, filters, and joins.
• table_functions: Mapping of table name to its functional role for the query.