Class ExternalDataSourceReadRouterImpl

Returns the cache TTL (in seconds) configured on the external data source — the basis for time-bounded caching of external reads. Unlike MJ-DB entities, external reads can't be event-invalidated (their data changes on the remote system), so callers cache them with a TTL instead. Implementations resolve the ExternalDataSource and return its DefaultCacheTTLSeconds (falling back to a sane default when unset). A return value of 0 signals "do not cache this source." Resolved through the engine's already-cached data source, so this is cheap to call on the read hot path.

Introspect the schema of an external data source (its tables/views/collections and their columns), delegating to the resolved driver's IntrospectSchema. Used by CodeGen to generate/sync EntityField metadata for external-backed entities — the remote analogue of reading INFORMATION_SCHEMA for an MJ-DB entity. schemaName narrows to a single schema/namespace when supplied. Reached via MJGlobal.ClassFactory so build-time consumers stay free of a hard dependency on the engine + driver SDKs.

Load a single record by primary key for an entity whose EntityInfo.ExternalDataSourceID is set. Composite-key aware: every field of CompositeKey is matched with a quoted, parameter-bound predicate at the driver boundary (so mixed-case / reserved-word PK columns work on case-sensitive external dialects). Returns a RunViewResult whose Results holds the single matched row (or is empty when not found) — mirroring RunViewExternal so the provider's Load path stays uniform.

Proxy a native-dialect MJ Query whose ExternalDataSourceID is set. Takes primitives (not the query entity) so this contract stays in @memberjunction/core without a circular dependency on core-entities. sql is the fully-rendered query text (MJ parameter templating already applied).

Proxy a RunView for an entity whose EntityInfo.ExternalDataSourceID is set.