Vanna query should be validated before executed

Is this a new feature, an improvement, or a change to existing functionality?

Change

How would you describe the priority of this feature request

Medium

Please provide a clear description of problem this feature solves

Feature Request: text2sql should not execute Destructive SQL Operations

Description

Currently, the Vanna plugin text2sql function appears to execute generated SQL queries directly (when execute_sql=true). While this is efficient for SELECT statements, it poses a significant risk when the model generates queries that modify, delete, or structure data (e.g., INSERT, UPDATE, DELETE, DROP, ALTER).

To improve security and prevent accidental data loss, I propose hardening the execution rules so that any non-read-only query is returned to the user as text for manual review and execution, rather than being run automatically.

Suggested Behavior

1. Generate any SQL statement
2. use vanna_instance.is_sql_valid(sql=... check if the SQL should be run.
   Conditional Execution:
   • Read-only (SELECT): Continue to execute and display results as usual.
   • Destructive/Modifying: Instead of executing, the plugin display the SQL with explanation to the user.
3. User Confirmation: User review the SQL and run it manually in her database terminal if it looks correct.

Use Case / Rationale

• Safety: Prevents the LLM from accidentally hallucinating a WHERE clause incorrectly on a DELETE or UPDATE statement.
• Security: Reduces the risk of "Prompt Injection" resulting in unauthorized data modification.

Describe your ideal solution

  @register_function(config_type=Text2SQLConfig, framework_wrappers=[LLMFrameworkEnum.LANGCHAIN])
  async def text2sql(config: Text2SQLConfig, builder: Builder):
      """Register the Text2SQL function with Vanna integration."""
      # ...
            sql = str(sql_result.get("sql", ""))
            explanation: str | None = sql_result.get("explanation")
            is_valid_sql = vanna_instance.is_sql_valid(sql)  # <------ add this check

            # If execute_sql is enabled, run the query
            if config.execute_sql and is_valid_sql:
                yield ResponseIntermediateStep(
                    id=str(uuid.uuid4()),
                    parent_id=parent_id,
                    type="markdown",
                    name="text2sql_status",
                    payload=StatusPayload(message="Executing SQL query...").model_dump_json(),
                )
                # Execute SQL and propagate errors
                # Note: run_sql is dynamically set as async function in setup_vanna_db_connection
                df = await vanna_instance.run_sql(sql)  # type: ignore[misc]
                logger.info(f"SQL executed successfully: {len(df)} rows returned")

            # Yield final result as Text2SQLOutput
            yield Text2SQLOutput(sql=sql, explanation=explanation)

Additional context

https://try.vanna.ai/docs/hardening-guide/

Code of Conduct

• I agree to follow this project's Code of Conduct
• I have searched the open feature requests and have found no duplicates for this feature request

Start at the text2sql function registered with Text2SQLConfig and inspect how it obtains sql_result, checks execute_sql, and calls vanna_instance.run_sql. Use the proposed vanna_instance.is_sql_valid check to distinguish read-only execution from SQL returned for review, while preserving the final Text2SQLOutput. Done means destructive or modifying statements are not executed automatically and SELECT statements still execute when configured.