Struct QueryProcessor 

pub struct QueryProcessor { /* private fields */ }

Processes queries through the full pipeline.

The processor holds references to the stores and provides a unified interface for executing queries in any supported language.

Example

use graphos_engine::query::processor::{QueryProcessor, QueryLanguage};

let processor = QueryProcessor::for_lpg(store);
let result = processor.process("MATCH (n:Person) RETURN n", QueryLanguage::Gql, None)?;

Implementations

impl QueryProcessor

pub fn for_lpg(store: Arc<LpgStore>) -> Self

Creates a new query processor for LPG queries.

pub fn for_lpg_with_tx( store: Arc<LpgStore>, tx_manager: Arc<TransactionManager>, ) -> Self

Creates a new query processor with a transaction manager.

pub fn with_tx_context(self, viewing_epoch: EpochId, tx_id: TxId) -> Self

Sets the transaction context for MVCC visibility.

This should be called when the processor is used within a transaction.

pub fn with_catalog(self, catalog: Arc<Catalog>) -> Self

Sets a custom catalog.

pub fn with_optimizer(self, optimizer: Optimizer) -> Self

Sets a custom optimizer.

pub fn process( &self, query: &str, language: QueryLanguage, params: Option<&QueryParams>, ) -> Result<QueryResult>

Processes a query string and returns results.

Pipeline:

1. Parse (language-specific parser → AST)
2. Translate (AST → LogicalPlan)
3. Bind (semantic validation)
4. Optimize (filter pushdown, join reorder, etc.)
5. Plan (logical → physical operators)
6. Execute (run operators, collect results)

Arguments

• query - The query string
• language - Which query language to use
• params - Optional query parameters for prepared statements

Errors

Returns an error if any stage of the pipeline fails.

pub fn lpg_store(&self) -> &Arc<LpgStore>

Returns a reference to the LPG store.

pub fn catalog(&self) -> &Arc<Catalog>

Returns a reference to the catalog.

pub fn optimizer(&self) -> &Optimizer

Returns a reference to the optimizer.

impl QueryProcessor

pub fn new() -> Self

👎Deprecated since 0.1.0: Use QueryProcessor::for_lpg() instead

Creates a new query processor (legacy API).

This creates a processor with an empty in-memory store. Prefer using QueryProcessor::for_lpg with an explicit store.

pub fn process_legacy(&self, query: &str) -> Result<QueryResult>

👎Deprecated since 0.1.0: Use process() with explicit language

Processes a query using default GQL language (legacy API).

Errors

Returns an error if the query fails.

pub fn tx_manager(&self) -> &Arc<TransactionManager>

Returns a reference to the transaction manager.

Trait Implementations

impl Default for QueryProcessor

fn default() -> Self

Returns the “default value” for a type.