aiondb-catalog-store

Concrete catalog backend. Holds the live CatalogState (schemas, tables, indexes, sequences, views, roles, privileges, functions, triggers, domains, user-defined types, casts, policies, rules, graph labels, statistics, tenants), runs DDL transactions against it, persists every mutation through a WAL handle, and rebuilds the state from WAL plus snapshots at startup. Implements the reader/writer traits exported by aiondb-catalog.

cargo

[dependencies]
aiondb-catalog-store = { path = "../aiondb-catalog-store" }

modules

module	purpose
`catalog_wal`	encode/decode catalog records on the WAL.
`recovery`	replay catalog WAL and snapshots at startup.
`replication`	export catalog state to followers.
`snapshot`	serialise `CatalogState` to a durable snapshot.

The remaining bootstrap, reader, sequences, system_tables, txn, and writer modules are private; they implement the CatalogReader / CatalogWriter / SequenceManager traits on CatalogStore and seed the bootstrap catalog (schema public, system tables).

key types

type	role
`CatalogStore`	the catalog backend; `Clone` shares state through `Arc`.
`CatalogStoreOptions`	constructor options (currently a unit marker).
`CatalogState`	the full in-memory catalog map (schemas, tables, indexes, ...).
`CatalogWalHandle`	mutex-wrapped `WalWriter` used by the catalog for durable DDL.
`SequenceValueState`	persisted `(current_value, is_called)` for one sequence.
`DEFAULT_SCHEMA_NAME`	the bootstrap public schema name.

CatalogStore implements the aiondb_catalog::CatalogReader, CatalogWriter, CatalogTxnParticipant, and SequenceManager traits.

construction

constructor	use
`CatalogStore::new()`	in-memory catalog (no WAL).
`CatalogStore::with_options(opts)`	same, with explicit options.
`CatalogStore::new_with_wal(wal)`	catalog with WAL-backed durability.
`CatalogStore::from_recovered(state, wal)`	rebuild after replay, keep WAL.
`CatalogStore::from_recovered_no_wal(state)`	rebuild without WAL.

CatalogWalHandle::open(WalConfig) opens the catalog WAL directory; CatalogWalHandle::new(WalWriter) wraps an existing writer. The handle exposes log, log_and_flush, flush, log_begin_txn, log_commit_txn, log_abort_txn, and wal_dir.

example

use std::sync::Arc;
use aiondb_catalog::{CatalogReader, QualifiedName};
use aiondb_catalog_store::{CatalogStore, CatalogWalHandle};
use aiondb_core::TxnId;
use aiondb_wal::WalConfig;

let wal_cfg = WalConfig {
    dir: "/var/lib/aiondb/catalog-wal".into(),
    ..Default::default()
};
let wal = Arc::new(CatalogWalHandle::open(wal_cfg).expect("open catalog wal"));
let catalog = CatalogStore::new_with_wal(wal);

let public = catalog
    .get_schema(TxnId::default(), &QualifiedName::unqualified("public"))
    .expect("read schema");
assert!(public.is_some());