Module catalog 

Schema metadata - what labels, properties, and indexes exist.

The catalog is the “dictionary” of your database. When you write (:Person), the catalog maps “Person” to an internal LabelId. This indirection keeps storage compact while names stay readable.

What it tracks	Why it matters
Labels	Maps “Person” → LabelId for efficient storage
Property keys	Maps “name” → PropertyKeyId
Edge types	Maps “KNOWS” → EdgeTypeId
Indexes	Which properties are indexed for fast lookups

Structs

Catalog

The database’s schema dictionary - maps names to compact internal IDs.

CatalogConstraintValidator

Validates schema constraints during mutation operations using the Catalog.

EdgeTypeDefinition

Definition of an edge type (relationship type schema).

GraphTypeDefinition

Definition of a graph type (constrains which node/edge types a graph allows).

IndexDefinition

Index definition.

NodeTypeDefinition

Definition of a node type (label schema).

ProcedureDefinition

Definition of a stored procedure.

SchemaCatalog

Schema constraints and type definitions.

TypedProperty

A typed property within a node or edge type definition.

Enums

CatalogError

Catalog-related errors.

IndexType

Type of index.

PropertyDataType

Data type for a typed property in a node or edge type definition.

TypeConstraint

A constraint on a node or edge type.