Classes and new fields

Classes, and what derived fields read

A class names a group of fields, such as everything about pay, for fields.classed(). Each entry is "Table.Field", ("Table", "Field") when a name holds a dot, fields.all(), or fields.labeled_like(...), which matches in every table.

A formula, lookup, or summary is in every class of the fields it reads, through any chain of them, including the fields a summary's filter uses. So deny.all(fields.classed("pay")) hides a formula of Hourly Rate, a lookup of that formula on another table, and a summary of the lookup. A formula that can't be read counts as reading every field of its table, and one that calls a function that reads other records counts as reading every field of the app.

flowchart TD
    subgraph Staff
        direction LR
        H["Hourly Rate<br/>class: pay"] --> D["Day Rate<br/>formula"]
    end
    subgraph Shifts
        L["Staff - Day Rate<br/>lookup"]
    end
    subgraph Projects
        T["Total Cost<br/>summary"]
    end
    D --> L --> T
    classDef pay fill:#e5393526,stroke:#e53935
    class H,D,L,T pay

Every field in the chain is in pay, so deny.all(fields.classed("pay")) hides all four, on all three tables.

A new formula, lookup, or summary may only read what the client may read, as anyone who can read it sees what it shows. The SDK's methods check this before sending one, and qb.request() can't make one.

Fields added after binding

The bound policy holds every table and field by ID, as Quickbase never reuses a field's ID within a table, so a rule can't come to mean another field. A renamed field keeps its rules until you bind again. A field added after binding gets new_fields:

new_fields	A new field is
"read", the default	Read, filtered, and sorted wherever a rule reads fields.all() or fields.new()
"hidden"	Hidden
A class's name	In that class, so the rules for the class apply

A new field is never writable until the policy is bound again, whatever the rules say.