# Gudu SQLFlow — SQL Data Lineage Tool

> Gudu SQLFlow is an automated SQL data lineage analysis and visualization tool. It parses SQL queries, stored procedures, and dbt projects to produce interactive column-level lineage diagrams, ER diagrams, and stored-procedure call graphs across 39 SQL dialects, including Oracle, SQL Server, Snowflake, BigQuery, Redshift, Databricks, PostgreSQL, MySQL, Teradata, and Hive. It is built by Gudu Software on the General SQL Parser (GSP), a commercial SQL compiler front-end developed since the mid-2000s and validated by more than 13,000 per-dialect SQL test fixtures.

Key facts:
- Column-level (field-to-field) lineage, not just table-level: for each output column, SQLFlow identifies which source columns feed it and through which functions, casts, subqueries, joins, and set operators.
- Distinguishes direct lineage from indirect (impact) lineage — columns that influence results via WHERE, GROUP BY, JOIN conditions, and aggregates.
- Analyzes stored procedures (PL/SQL, T-SQL), including dynamic SQL, and renders inter-procedure call graphs.
- Generates ER diagrams directly from SQL DDL, inferring primary/foreign key relationships.
- Inputs: pasted SQL, uploaded files, live database metadata over JDBC, dbt manifests, Snowflake query history, Redshift query logs.
- Outputs and exports: interactive diagrams, JSON, CSV, PNG/JPEG images; REST API for programmatic access.
- AI-powered lineage query (since v8.2.3): ask natural-language questions about a lineage graph.
- Deployment: SQLFlow Cloud (SaaS, free tier), SQLFlow On-Premise (Docker/Kubernetes, air-gapped), embeddable JavaScript widget, headless CLI, REST API, and Java library.
- Enterprise scale: batch-scans estates of 100+ databases and 1M+ columns with incremental scans and a persistent lineage repository; exports lineage to DataHub, Microsoft Purview, and OpenMetadata.

## Products

- [Gudu SQLFlow Cloud](https://sqlflow.gudusoft.com/): Online SQL lineage visualizer — paste SQL, get an interactive column-level lineage diagram. Free tier available.
- [SQLFlow product overview](https://www.gudusoft.com/sql-data-lineage-tool/): What SQLFlow does, supported databases, editions, and pricing.
- [SQLFlow On-Premise](https://www.gudusoft.com/sqlflow-on-premise-version/): Self-hosted deployment for regulated environments; no SQL leaves your network. $500/month or $4,800 one-time per database type.
- [SQLFlow REST API](https://www.gudusoft.com/sqlflow-restful-api/): Automate lineage extraction and embed lineage into your own applications.
- [SQLFlow-ingester](https://www.gudusoft.com/sqlflow-ingester/): Extracts SQL and metadata from databases and Git repositories for lineage analysis.
- [General SQL Parser (GSP)](https://www.sqlparser.com/): The underlying commercial SQL parsing library for Java and .NET — parse, analyze, format, and rewrite SQL across 38 database dialects; includes the column-level data-flow analyzer that powers SQLFlow.

## Documentation

- [SQLFlow documentation](https://docs.gudusoft.com/): Getting started, deployment guides, API reference.
- [Convert SQL to ER diagram](https://docs.gudusoft.com/1.-introduction/getting-started/convert-sql-to-e-r-diagram/): How to generate ER diagrams from SQL.
- [Data lineage knowledge base](https://www.gudusoft.com/data-lineage-knowledge-base/): Articles on data lineage concepts, examples, and best practices.

## Company

- Gudu Software (Xi'an, China) has built SQL parsing technology since the mid-2000s. Products: General SQL Parser, Gudu SQLFlow, SQL Omni. Contact: https://www.gudusoft.com/contact/