Struct SchemaGraph 

pub struct SchemaGraph {
    pub schema: Schema,
    pub parents: Vec<Vec<TableId>>,
    pub children: Vec<Vec<TableId>>,
}

Schema dependency graph built from foreign key relationships.

The graph represents parent → child relationships where:

• A parent is a table referenced by another table’s FK
• A child is a table that has an FK referencing another table

This ordering allows processing parents before children, ensuring that when sampling/filtering children, parent data is already available.

Fields

schema: Schema

The underlying schema

parents: Vec<Vec<TableId>>

For each table, list of parent tables (tables this table references via FK)

children: Vec<Vec<TableId>>

For each table, list of child tables (tables that reference this table via FK)

Implementations

impl SchemaGraph

pub fn from_schema(schema: Schema) -> Self

Build a dependency graph from a schema

pub fn len(&self) -> usize

Get the number of tables in the graph

pub fn is_empty(&self) -> bool

Check if the graph is empty

pub fn table_name(&self, id: TableId) -> Option<&str>

Get the table name for a table ID

pub fn has_self_reference(&self, id: TableId) -> bool

Check if a table has a self-referential FK

pub fn self_referential_tables(&self) -> Vec<TableId>

Get tables that have self-referential FKs

pub fn topo_sort(&self) -> TopoSortResult

Perform topological sort using Kahn’s algorithm.

Returns tables in dependency order (parents before children). Tables that are part of cycles are returned separately.

pub fn processing_order(&self) -> (Vec<TableId>, Vec<TableId>)

Get processing order for sampling/sharding.

Returns all tables in order: first the topologically sorted acyclic tables, then the cyclic tables (which need special handling).

pub fn is_ancestor(&self, ancestor: TableId, descendant: TableId) -> bool

Check if table A is an ancestor of table B (A is referenced by B directly or transitively)

pub fn ancestors(&self, id: TableId) -> Vec<TableId>

Get all ancestor tables of a given table (tables it depends on, directly or transitively)

pub fn descendants(&self, id: TableId) -> Vec<TableId>

Get all descendant tables of a given table (tables that depend on it)

pub fn root_tables(&self) -> Vec<TableId>

Get root tables (tables with no parents/dependencies)

pub fn leaf_tables(&self) -> Vec<TableId>

Get leaf tables (tables with no children/dependents)

Trait Implementations

impl Debug for SchemaGraph

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.