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Function: collectQueryClasses()

function collectQueryClasses(ast): string[];

Defined in: packages/client/src/core/query-engine/classes.ts:41

Collects the class names a parsed query reads.

Deliberately generic: rather than enumerating the node types that can hold a nested query - scalar_subquery, exists_expr, the right-hand side of IN - it walks the whole graph and harvests every select node it finds. A new subquery form is then covered on the day it is added, rather than on the day someone notices a stale list.

Parameters​

ParameterTypeDescription
ast( | SelectAST | UnionAST)[]The ast from ClientStack.query.

Returns​

string[]

The class names read, or null when the query reads a source that is not a named class. That distinction is the contract: [] means this query reads nothing - SELECT 1 - and it is safe to subscribe to nothing; null means I cannot account for this, and the caller should fail open rather than watch an incomplete set.

Example​

const { rows, ast } = await stack.query("SELECT * FROM Task JOIN Project ON …");
collectQueryClasses(ast);         // ["Task", "Project"]
collectQueryClasses([]);          // []   - reads nothing
collectQueryClasses(null);        // null - unknown, fail open