inbq

A library for parsing BigQuery queries and extracting schema-aware, column-level lineage.

Features

• Parse BigQuery queries into well-structured ASTs with easy-to-navigate nodes.
• Extract schema-aware, column-level lineage.
• Trace data flow through nested structs and arrays.
• Capture referenced columns and the specific query components (e.g., select, where, joins) they appear in.
• Support both single and multi-statement queries and procedural language constructs.
• Built for speed and efficiency, with lightweight Python bindings that add minimal overhead.

Python

Install

pip install inbq

Example

import inbq

catalog = {"schema_objects": []}

def add_table(name: str, columns: list[tuple[str, str]]) -> None:
    catalog["schema_objects"].append({
        "name": name,
        "kind": {
            "table": {
                "columns": [{"name": name, "dtype": dtype} for name, dtype in columns]
            }
        }
    })

add_table("project.dataset.out", [("id", "int64"), ("val", "float64")])
add_table("project.dataset.t1", [("id", "int64"), ("x", "float64")])
add_table("project.dataset.t2", [("id", "int64"), ("s", "struct<source string, x float64>")])

query = """
declare default_val float64 default (select min(val) from project.dataset.out);

insert into `project.dataset.out`
select
    id,
    if(x is null or s.x is null, default_val, x + s.x)
from `project.dataset.t1` inner join `project.dataset.t2` using (id)
where s.source = "baz";
"""

pipeline = (
  inbq.Pipeline()
    .config(raise_exception_on_error=False, parallel=True)
    .parse()
    .extract_lineage(catalog=catalog, include_raw=False)
)
pipeline_output = inbq.run_pipeline(sqls=[query], pipeline=pipeline)

for ast, output_lineage in zip(pipeline_output.asts, pipeline_output.lineages):
    print(f"{ast=}")
    print("\nLineage:")
    for object in output_lineage.lineage.objects:
        print("Inputs:")
        for node in object.nodes:
            print(
                f"{object.name}->{node.name} <- {[f'{input_node.obj_name}->{input_node.node_name}' for input_node in node.inputs]}"
            )

        print("\nSide inputs:")
        for node in object.nodes:
            print(
                f"""{object.name}->{node.name} <- {[f"{input_node.obj_name}->{input_node.node_name} @ {','.join(input_node.sides)}" for input_node in node.side_inputs]}"""
            )

    print("\nReferenced columns:")
    for object in output_lineage.referenced_columns.objects:
        for node in object.nodes:
            print(f"{object.name}->{node.name} referenced in {node.referenced_in}")
# Prints:
# ast=Ast(...)

# Lineage:
# Inputs:
# project.dataset.out->id <- ['project.dataset.t2->id', 'project.dataset.t1->id']
# project.dataset.out->val <- ['project.dataset.t2->s.x', 'project.dataset.t1->x', 'project.dataset.out->val']
#
# Side inputs:
# project.dataset.out->id <- ['project.dataset.t2->s.source @ where', 'project.dataset.t2->id @ join', 'project.dataset.t1->id @ join']
# project.dataset.out->val <- ['project.dataset.t2->s.source @ where', 'project.dataset.t2->id @ join', 'project.dataset.t1->id @ join']
#
# Referenced columns:
# project.dataset.out->val referenced in ['default_var', 'select']
# project.dataset.t1->id referenced in ['join', 'select']
# project.dataset.t1->x referenced in ['select']
# project.dataset.t2->id referenced in ['join', 'select']
# project.dataset.t2->s.x referenced in ['select']
# project.dataset.t2->s.source referenced in ['where']

Rust

Install

cargo add inbq

Example

use inbq::{
    lineage::{
        catalog::{Catalog, Column, SchemaObject, SchemaObjectKind},
        extract_lineage,
    },
    parser::Parser,
    scanner::Scanner,
};

fn column(name: &str, dtype: &str) -> Column {
    Column {
        name: name.to_owned(),
        dtype: dtype.to_owned(),
    }
}

fn main() -> anyhow::Result<()> {
    env_logger::init();

    let sql = r#"
        declare default_val float64 default (select min(val) from project.dataset.out);

        insert into `project.dataset.out`
        select
            id,
            if(x is null or s.x is null, default_val, x + s.x)
        from `project.dataset.t1` inner join `project.dataset.t2` using (id)
        where s.source = "baz";
    "#;
    let mut scanner = Scanner::new(sql);
    scanner.scan()?;
    let mut parser = Parser::new(scanner.tokens());
    let ast = parser.parse()?;
    println!("Syntax Tree: {:?}", ast);

    let data_catalog = Catalog {
        schema_objects: vec![
            SchemaObject {
                name: "project.dataset.out".to_owned(),
                kind: SchemaObjectKind::Table {
                    columns: vec![column("id", "int64"), column("val", "int64")],
                },
            },
            SchemaObject {
                name: "project.dataset.t1".to_owned(),
                kind: SchemaObjectKind::Table {
                    columns: vec![column("id", "int64"), column("x", "float64")],
                },
            },
            SchemaObject {
                name: "project.dataset.t2".to_owned(),
                kind: SchemaObjectKind::Table {
                    columns: vec![
                        column("id", "int64"),
                        column("s", "struct<source string, x float64>"),
                    ],
                },
            },
        ],
    };

    let lineage = extract_lineage(&[&ast], &data_catalog, false, true)
        .pop()
        .unwrap()?;

    println!("\nLineage: {:?}", lineage.lineage);
    println!("\nReferenced columns: {:?}", lineage.referenced_columns);
    Ok(())
}

Command Line Interface

Install binary

cargo install inbq

Extract Lineage

1. Prepare your data catalog: create a JSON file (e.g., catalog.json) that defines the schema for all tables and views referenced in your SQL queries.

2. Run inbq: pass the catalog file and your SQL file(s) to the inbq lineage command.

inbq extract-lineage \
    --pretty \
    --catalog ./examples/lineage/catalog.json  \
    ./examples/lineage/query.sql

The output is written to stdout.