Export and document subtract, multiply, divide math functions #1151

KyleAMathews · 2026-01-18T05:35:33Z

Summary

Add subtract, multiply, and divide math functions to enable computed columns in queries. This unlocks ranking algorithms and dynamic calculations directly in select and orderBy clauses without pre-computing values.

Approach

Extended the existing math function pattern established by add(). Each function:

Takes two numeric operands (field refs, literals, or nested expressions)
Returns a BasicExpression<number> with proper nullability inference via BinaryNumericReturnType
Compiles to the corresponding IR node for execution

// Functions follow the same pattern as add()
export function subtract<T1, T2>(left: T1, right: T2): BinaryNumericReturnType<T1, T2> {
  return new Func(`subtract`, [toExpression(left), toExpression(right)])
}

Key design choice: Functions can be nested for complex calculations:

// (salary * 1.1) - 500
subtract(multiply(employees.salary, 1.1), 500)

Key Invariants

Type safety preserved — Nullability propagates correctly (if either operand can be null/undefined, result can be too)
Composability — Functions nest arbitrarily without special handling
Consistent pattern — All four arithmetic functions share identical structure with add()

Non-goals

Division by zero handling — Left to the runtime/backend (returns null per SQL semantics)
Operator syntax — No a + b syntax; explicit function calls keep the IR clean

Verification

pnpm test --filter @tanstack/db

Tests cover:

Each function individually (subtract, multiply, divide)
Nested composition (e.g., subtract(multiply(...), ...))
Usage in orderBy clauses

Files Changed

File	Change
`packages/db/src/query/builder/functions.ts`	Add `subtract`, `multiply`, `divide` functions
`packages/db/src/query/index.ts`	Export new functions
`packages/db/tests/query/builder/functions.test.ts`	Add tests for new functions
`docs/guides/live-queries.md`	Document functions + computed orderBy example
`.changeset/add-math-functions.md`	Changeset for release

🤖 Generated with Claude Code

Add missing math functions that were implemented in evaluators but not exported. These enable computed columns in orderBy for ranking algorithms like HN-style scoring that balances recency and rating. - Add subtract(a, b) function - Add multiply(a, b) function - Add divide(a, b) function (with null on divide-by-zero) - Export from query/index.ts - Add to operators list - Add comprehensive tests including orderBy usage

- Add documentation for new math functions in live-queries.md - Include example of computed columns in orderBy for ranking algorithms - Add changeset for the new minor feature

changeset-bot · 2026-01-18T05:35:37Z

🦋 Changeset detected

Latest commit: 287a1ff

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 12 packages

Name	Type
@tanstack/db	Patch
@tanstack/angular-db	Patch
@tanstack/electric-db-collection	Patch
@tanstack/offline-transactions	Patch
@tanstack/powersync-db-collection	Patch
@tanstack/query-db-collection	Patch
@tanstack/react-db	Patch
@tanstack/rxdb-db-collection	Patch
@tanstack/solid-db	Patch
@tanstack/svelte-db	Patch
@tanstack/trailbase-db-collection	Patch
@tanstack/vue-db	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

pkg-pr-new · 2026-01-18T05:38:12Z

More templates

@tanstack/angular-db

npm i https://pkg.pr.new/@tanstack/angular-db@1151

@tanstack/db

npm i https://pkg.pr.new/@tanstack/db@1151

@tanstack/db-ivm

npm i https://pkg.pr.new/@tanstack/db-ivm@1151

@tanstack/electric-db-collection

npm i https://pkg.pr.new/@tanstack/electric-db-collection@1151

@tanstack/offline-transactions

npm i https://pkg.pr.new/@tanstack/offline-transactions@1151

@tanstack/powersync-db-collection

npm i https://pkg.pr.new/@tanstack/powersync-db-collection@1151

@tanstack/query-db-collection

npm i https://pkg.pr.new/@tanstack/query-db-collection@1151

@tanstack/react-db

npm i https://pkg.pr.new/@tanstack/react-db@1151

@tanstack/rxdb-db-collection

npm i https://pkg.pr.new/@tanstack/rxdb-db-collection@1151

@tanstack/solid-db

npm i https://pkg.pr.new/@tanstack/solid-db@1151

@tanstack/svelte-db

npm i https://pkg.pr.new/@tanstack/svelte-db@1151

@tanstack/trailbase-db-collection

npm i https://pkg.pr.new/@tanstack/trailbase-db-collection@1151

@tanstack/vue-db

npm i https://pkg.pr.new/@tanstack/vue-db@1151

commit: 287a1ff

github-actions · 2026-01-18T05:38:49Z

Size Change: +100 B (+0.11%)

Total Size: 90.6 kB

Filename	Size	Change
`./packages/db/dist/esm/index.js`	2.73 kB	+40 B (+1.48%)
`./packages/db/dist/esm/query/builder/functions.js`	793 B	+60 B (+8.19%)	🔍

ℹ️ View Unchanged

Filename	Size
`./packages/db/dist/esm/collection/change-events.js`	1.39 kB
`./packages/db/dist/esm/collection/changes.js`	1.19 kB
`./packages/db/dist/esm/collection/events.js`	388 B
`./packages/db/dist/esm/collection/index.js`	3.32 kB
`./packages/db/dist/esm/collection/indexes.js`	1.1 kB
`./packages/db/dist/esm/collection/lifecycle.js`	1.67 kB
`./packages/db/dist/esm/collection/mutations.js`	2.34 kB
`./packages/db/dist/esm/collection/state.js`	3.46 kB
`./packages/db/dist/esm/collection/subscription.js`	3.62 kB
`./packages/db/dist/esm/collection/sync.js`	2.38 kB
`./packages/db/dist/esm/deferred.js`	207 B
`./packages/db/dist/esm/errors.js`	4.49 kB
`./packages/db/dist/esm/event-emitter.js`	748 B
`./packages/db/dist/esm/indexes/auto-index.js`	742 B
`./packages/db/dist/esm/indexes/base-index.js`	766 B
`./packages/db/dist/esm/indexes/btree-index.js`	1.93 kB
`./packages/db/dist/esm/indexes/lazy-index.js`	1.1 kB
`./packages/db/dist/esm/indexes/reverse-index.js`	513 B
`./packages/db/dist/esm/local-only.js`	837 B
`./packages/db/dist/esm/local-storage.js`	2.1 kB
`./packages/db/dist/esm/optimistic-action.js`	359 B
`./packages/db/dist/esm/paced-mutations.js`	496 B
`./packages/db/dist/esm/proxy.js`	3.75 kB
`./packages/db/dist/esm/query/builder/index.js`	4.08 kB
`./packages/db/dist/esm/query/builder/ref-proxy.js`	1.05 kB
`./packages/db/dist/esm/query/compiler/evaluators.js`	1.42 kB
`./packages/db/dist/esm/query/compiler/expressions.js`	430 B
`./packages/db/dist/esm/query/compiler/group-by.js`	1.87 kB
`./packages/db/dist/esm/query/compiler/index.js`	1.96 kB
`./packages/db/dist/esm/query/compiler/joins.js`	2 kB
`./packages/db/dist/esm/query/compiler/order-by.js`	1.45 kB
`./packages/db/dist/esm/query/compiler/select.js`	1.06 kB
`./packages/db/dist/esm/query/expression-helpers.js`	1.43 kB
`./packages/db/dist/esm/query/ir.js`	673 B
`./packages/db/dist/esm/query/live-query-collection.js`	360 B
`./packages/db/dist/esm/query/live/collection-config-builder.js`	5.4 kB
`./packages/db/dist/esm/query/live/collection-registry.js`	264 B
`./packages/db/dist/esm/query/live/collection-subscriber.js`	1.93 kB
`./packages/db/dist/esm/query/live/internal.js`	145 B
`./packages/db/dist/esm/query/optimizer.js`	2.56 kB
`./packages/db/dist/esm/query/predicate-utils.js`	2.97 kB
`./packages/db/dist/esm/query/subset-dedupe.js`	921 B
`./packages/db/dist/esm/scheduler.js`	1.3 kB
`./packages/db/dist/esm/SortedMap.js`	1.3 kB
`./packages/db/dist/esm/strategies/debounceStrategy.js`	247 B
`./packages/db/dist/esm/strategies/queueStrategy.js`	428 B
`./packages/db/dist/esm/strategies/throttleStrategy.js`	246 B
`./packages/db/dist/esm/transactions.js`	2.9 kB
`./packages/db/dist/esm/utils.js`	924 B
`./packages/db/dist/esm/utils/browser-polyfills.js`	304 B
`./packages/db/dist/esm/utils/btree.js`	5.61 kB
`./packages/db/dist/esm/utils/comparison.js`	852 B
`./packages/db/dist/esm/utils/cursor.js`	457 B
`./packages/db/dist/esm/utils/index-optimization.js`	1.51 kB
`./packages/db/dist/esm/utils/type-guards.js`	157 B

_{compressed-size-action::db-package-size}

github-actions · 2026-01-18T05:39:26Z

Size Change: 0 B

Total Size: 3.47 kB

ℹ️ View Unchanged

Filename	Size
`./packages/react-db/dist/esm/index.js`	225 B
`./packages/react-db/dist/esm/useLiveInfiniteQuery.js`	1.17 kB
`./packages/react-db/dist/esm/useLiveQuery.js`	1.12 kB
`./packages/react-db/dist/esm/useLiveSuspenseQuery.js`	559 B
`./packages/react-db/dist/esm/usePacedMutations.js`	401 B

_{compressed-size-action::react-db-package-size}

claude added 2 commits January 18, 2026 00:57

docs: document subtract, multiply, divide math functions

4874663

- Add documentation for new math functions in live-queries.md - Include example of computed columns in orderBy for ranking algorithms - Add changeset for the new minor feature

ci: apply automated fixes

287a1ff

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Export and document subtract, multiply, divide math functions #1151

Export and document subtract, multiply, divide math functions #1151

KyleAMathews commented Jan 18, 2026 •

edited

Loading

Uh oh!

changeset-bot bot commented Jan 18, 2026 •

edited

Loading

Uh oh!

pkg-pr-new bot commented Jan 18, 2026

Uh oh!

github-actions bot commented Jan 18, 2026

Uh oh!

github-actions bot commented Jan 18, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Export and document subtract, multiply, divide math functions #1151

Are you sure you want to change the base?

Export and document subtract, multiply, divide math functions #1151

Conversation

KyleAMathews commented Jan 18, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Approach

Key Invariants

Non-goals

Verification

Files Changed

Uh oh!

changeset-bot bot commented Jan 18, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

🦋 Changeset detected

Uh oh!

pkg-pr-new bot commented Jan 18, 2026

Uh oh!

github-actions bot commented Jan 18, 2026

Uh oh!

github-actions bot commented Jan 18, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

KyleAMathews commented Jan 18, 2026 •

edited

Loading

changeset-bot bot commented Jan 18, 2026 •

edited

Loading