Struct PostgresIntrospector 

pub struct PostgresIntrospector { /* private fields */ }

PostgreSQL introspector for fact table metadata.

Implementations

impl PostgresIntrospector

pub const fn new(pool: Pool) -> Self

Create new PostgreSQL introspector from connection pool.

impl PostgresIntrospector

pub async fn get_indexed_nested_columns( &self, view_name: &str, ) -> Result<HashSet<String>>

Get indexed columns for a view/table that match the nested path naming convention.

This method introspects the database to find columns that follow the FraiseQL indexed column naming conventions:

• Human-readable: items__product__category__code (double underscore separated)
• Entity ID format: f{entity_id}__{field_name} (e.g., f200100__code)

These columns are created by DBAs to optimize filtering on nested GraphQL paths by avoiding JSONB extraction at runtime.

Arguments

• view_name - Name of the view or table to introspect

Returns

Set of column names that match the indexed column naming conventions.

Errors

Returns FraiseQLError::ConnectionPool if a connection cannot be acquired, or FraiseQLError::Database if the query fails.

Example

use fraiseql_db::postgres::PostgresIntrospector;
use deadpool_postgres::Pool;

let introspector = PostgresIntrospector::new(pool);
let indexed_cols = introspector.get_indexed_nested_columns("v_order_items").await?;
// Returns: {"items__product__category__code", "f200100__code", ...}

pub async fn get_view_columns(&self, view_name: &str) -> Result<Vec<String>>

Get all column names for a view/table.

Arguments

• view_name - Name of the view or table to introspect

Returns

List of all column names in the view/table.

Errors

Returns FraiseQLError::ConnectionPool if a connection cannot be acquired, or FraiseQLError::Database if the query fails.

Trait Implementations

impl DatabaseIntrospector for PostgresIntrospector

async fn list_fact_tables(&self) -> Result<Vec<String>>

List all fact tables in the database (tables starting with “tf_”).

async fn get_columns( &self, table_name: &str, ) -> Result<Vec<(String, String, bool)>>

Query column information for a table.

async fn get_indexed_columns(&self, table_name: &str) -> Result<Vec<String>>

Query indexes for a table.

fn database_type(&self) -> DatabaseType

Get database type (for SQL type parsing).

async fn get_sample_jsonb( &self, table_name: &str, column_name: &str, ) -> Result<Option<Value>>

Get sample JSONB data from a column to extract dimension paths.

async fn list_relations(&self) -> Result<Vec<RelationInfo>>

List all relations (tables and views) in the database.

async fn get_sample_json_rows( &self, _table_name: &str, _column_name: &str, _limit: usize, ) -> Result<Vec<Value>>

Get sample JSON rows from a column for schema inference.