State Consumers and Relations

What can we fetch and what not? Starting at the "starting table", PL can go along the directional relations (start --> node2 --> node3) any number of nodes and right-JOIN them to a single query. It can also go one step to the opposite direction (start --> node2 <-- node3), left-JOINING node3, but after such step, it cannot continue on this path (anything related to node3 won't be accessible within this query). Here are examples of what is currently supported by the fetcher and what is not.

• AdEntity may fetch fields from CampaignEntity and AccountEntity including from table "account_credentials" which is a secondary table of the account entity.
• AdEntity may not fetch fields from table "account_cred_ext", which is a secondary table of a secondary table of the parent account entity.
• CampaignEntity may fetch fields of AdEntity. This feature is called "Fetch Many" and is not recommended to be used inside PL flow components (validators, enrichers, etc). It is intended to be used by the PL query language. To access the child entity from the resulted parent entity, use the method getMany(AdEntity.INSTANCE).
• AccountEntity may not fetch fields of AdEntity. The fetch many feature is not yet recursive and can only handle a single hierarchy level.