Type Alias: ApplyJoinOptionalityToMergedSchema<TExistingSchema, TNewSchema, TJoinType, TFromSourceName>

type ApplyJoinOptionalityToMergedSchema<TExistingSchema, TNewSchema, TJoinType, TFromSourceName> = { [K in keyof TExistingSchema]: K extends TFromSourceName ? TJoinType extends "right" | "full" ? TExistingSchema[K] | undefined : TExistingSchema[K] : TExistingSchema[K] } & { [K in keyof TNewSchema]: TJoinType extends "left" | "full" ? TNewSchema[K] | undefined : TNewSchema[K] };

type ApplyJoinOptionalityToMergedSchema<TExistingSchema, TNewSchema, TJoinType, TFromSourceName> = { [K in keyof TExistingSchema]: K extends TFromSourceName ? TJoinType extends "right" | "full" ? TExistingSchema[K] | undefined : TExistingSchema[K] : TExistingSchema[K] } & { [K in keyof TNewSchema]: TJoinType extends "left" | "full" ? TNewSchema[K] | undefined : TNewSchema[K] };

Defined in: packages/db/src/query/builder/types.ts:622

ApplyJoinOptionalityToMergedSchema - Applies optionality rules when merging schemas

This type implements the SQL join optionality semantics:

For Existing Tables:

RIGHT JOIN or FULL JOIN: Main table (from fromSourceName) becomes optional
Other join types: Existing tables keep their current optionality
Previously joined tables: Keep their already-applied optionality

For New Tables:

LEFT JOIN or FULL JOIN: New table becomes optional
INNER JOIN or RIGHT JOIN: New table remains required

Examples:

sql

FROM users LEFT JOIN orders  -- orders becomes optional
FROM users RIGHT JOIN orders -- users becomes optional
FROM users FULL JOIN orders  -- both become optional
FROM users INNER JOIN orders -- both remain required

FROM users LEFT JOIN orders  -- orders becomes optional
FROM users RIGHT JOIN orders -- users becomes optional
FROM users FULL JOIN orders  -- both become optional
FROM users INNER JOIN orders -- both remain required

The intersection (&) ensures both existing and new schemas are merged into a single type while preserving all table references.