Module lineage 

Column Lineage Tracking

This module provides functionality to track column lineage through SQL queries, building a graph of how columns flow from source tables to the result set. Supports UNION/INTERSECT/EXCEPT, CTEs, derived tables, subqueries, and star expansion.

Structs

LineageNode

A node in the column lineage graph

LineageWalker

Iterator for walking the lineage graph

QueryOutput

The ordered output description of a query.

SetBranch

Metadata describing a lineage node’s position in an immediate set operation.

Enums

OutputColumn

One entry in a query’s ordered output description.

SetOperator

The set operator that owns an immediate lineage branch.

Functions

collect_source_tables

Recursively collect source table names from lineage graph

expand_cte_stars

Expand SELECT * in CTEs by walking CTE definitions in order and propagating resolved column lists. This handles nested CTEs (e.g., cte2 AS (SELECT * FROM cte1)) which qualify_columns cannot resolve because it processes each SELECT independently.

get_source_tables

Get all source tables from a lineage graph

lineage

Build the lineage graph for a column in a SQL query

lineage_at

Build the lineage graph for the column at a zero-based output ordinal.

lineage_at_with_schema

Build schema-aware lineage for the column at a zero-based output ordinal.

lineage_with_schema

Build the lineage graph for a column in a SQL query using optional schema metadata.

output_columns

Return the ordered output description of a query.

output_columns_with_schema

Return the ordered output description of a query after schema-aware expansion.