Make indexing opt-in #950

KyleAMathews · 2025-12-02T19:18:36Z

No description provided.

changeset-bot · 2025-12-02T19:18:40Z

🦋 Changeset detected

Latest commit: f2796da

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

This PR includes changesets to release 15 packages

Name	Type
@tanstack/db	Minor
@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
todos	Patch
@tanstack/db-example-paced-mutations-demo	Patch
offline-transactions-react-native	Patch

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pkg-pr-new · 2025-12-02T19:22:39Z

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commit: f2796da

github-actions · 2025-12-02T19:23:13Z

Size Change: +1.94 kB (+2.14%)

Total Size: 92.5 kB

Filename	Size	Change
`./packages/db/dist/esm/collection/index.js`	3.14 kB	-183 B (-5.51%)	✅
`./packages/db/dist/esm/collection/indexes.js`	845 B	-253 B (-23.04%)	🎉
`./packages/db/dist/esm/collection/lifecycle.js`	1.58 kB	-86 B (-5.16%)	✅
`./packages/db/dist/esm/collection/subscription.js`	3.66 kB	+35 B (+0.97%)
`./packages/db/dist/esm/index.js`	2.67 kB	-23 B (-0.85%)
`./packages/db/dist/esm/indexes/auto-index.js`	935 B	+193 B (+26.01%)	🚨
`./packages/db/dist/esm/indexes/base-index.js`	729 B	-37 B (-4.83%)	✅
`./packages/db/dist/esm/indexes/btree-index.js`	0 B	-1.93 kB (removed)	🏆
`./packages/db/dist/esm/indexes/index-registry.js`	797 B	+797 B (new file)	🆕
`./packages/db/dist/esm/indexes/lazy-index.js`	0 B	-1.1 kB (removed)	🏆
`./packages/db/dist/esm/indexes/read-optimized-index.js`	1.93 kB	+1.93 kB (new file)	🆕
`./packages/db/dist/esm/indexes/write-optimized-index.js`	1.94 kB	+1.94 kB (new file)	🆕
`./packages/db/dist/esm/indexing.js`	371 B	+371 B (new file)	🆕
`./packages/db/dist/esm/query/builder/functions.js`	714 B	-19 B (-2.59%)
`./packages/db/dist/esm/query/compiler/order-by.js`	1.45 kB	-5 B (-0.34%)
`./packages/db/dist/esm/query/live/collection-subscriber.js`	1.97 kB	+36 B (+1.86%)
`./packages/db/dist/esm/utils/array-utils.js`	273 B	+273 B (new file)	🆕

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/mutations.js`	2.34 kB
`./packages/db/dist/esm/collection/state.js`	3.49 kB
`./packages/db/dist/esm/collection/sync.js`	2.4 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/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/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/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 · 2025-12-02T19:23:47Z

Size Change: 0 B

Total Size: 3.7 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`	1.34 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}

kevin-dp

I left some comments that i would like to see addressed. Nothing major. There are no unit tests for the new BasicIndex. We should add unit tests.

packages/db/src/indexes/auto-index.ts

packages/db/src/indexes/basic-index.ts

packages/db/src/indexes/read-optimized-index.ts

packages/db/src/indexes/basic-index.ts

packages/db/src/indexes/read-optimized-index.ts

packages/db/src/indexes/basic-index.ts

packages/db/src/indexes/index-options.ts

kevin-dp · 2025-12-11T09:23:51Z

packages/db/src/indexes/index-registry.ts

+// Dev mode detection settings - ON by default in non-production
+let devModeConfig: IndexDevModeConfig = {
+  enabled: true,
+  collectionSizeThreshold: 1000,


This threshold seems arbitrary. Going through an non-indexed collection of 1000 rows should be pretty fast. I guess modern machines can easily go to perhaps 1M rows before it really becomes slow and needs indexes. Time-based suggestions (slowQueryThresholdMs) makes much more sense imo.

This POC explores making indexing a tree-shakeable opt-in feature to reduce default bundle size. Key changes: - Create new `@tanstack/db/indexing` entry point for BTreeIndex and related utils - Add index registry to replace hard-coded BTreeIndex defaults - Add dev-mode auto-detection for when indexes would help (collection size, slow queries) - Remove BTreeIndex value export from main entry (types still exported) Bundle size improvements when NOT using indexing: - Minified: ~15 KB saved (6.9%) - Gzipped: ~5.4 KB saved (8.5%) Usage after this change: ```ts // Option 1: Enable indexing globally import { enableIndexing } from '@tanstack/db/indexing' enableIndexing() // Option 2: Use explicit index type (best for tree-shaking) import { BTreeIndex } from '@tanstack/db/indexing' collection.createIndex((row) => row.userId, { indexType: BTreeIndex }) // Dev mode for index suggestions import { configureIndexDevMode } from '@tanstack/db' configureIndexDevMode({ enabled: true, collectionSizeThreshold: 100 }) ``` Note: Additional savings (~25KB more) possible by making index-optimization.ts lazy-loaded, but would require more extensive refactoring of change-events.ts and order-by.ts.

…y default Breaking change: autoIndex now defaults to 'off' instead of 'eager'. This reduces default bundle size by not requiring indexing code. Changes: - autoIndex defaults to 'off' - users must explicitly enable or add indexes - Dev mode suggestions are ON by default (in non-production) to help developers identify when indexes would improve performance - Updated tests to reflect new default behavior Users who want auto-indexing can either: 1. Set autoIndex: 'eager' on individual collections 2. Import and register BTreeIndex globally: ```ts import { enableIndexing } from '@tanstack/db/indexing' enableIndexing() ``` Dev mode will warn in console when queries could benefit from indexes, and this will also be available in devtools.

Most collections won't have perf issues until much larger sizes. Slow query detection (10ms) is the more actionable metric.

- Add MapIndex for equality lookups (eq, in) without BTree overhead - Change enableIndexing() to use MapIndex by default - Add enableBTreeIndexing() for ORDER BY optimization on large collections - BTreeIndex is only needed for sorted iteration (10k+ items with ORDER BY) Bundle size impact: - MapIndex: ~5 KB (~1.3 KB gzipped) - BTreeIndex: ~33 KB (~7.8 KB gzipped) - Savings with MapIndex: ~27 KB (~6 KB gzipped)

…ndexType - Add BasicIndex using Map + sorted Array for both equality and range queries - Remove registry pattern - pass defaultIndexType to collection constructor instead - Remove lazy index infrastructure (LazyIndexWrapper, IndexProxy) - Simplify indexing.ts entry point to just export BasicIndex and BTreeIndex - Update all tests to explicitly set defaultIndexType where needed - Update changeset to reflect simplified approach Breaking changes: - createIndex() requires defaultIndexType on collection or indexType in config - enableIndexing()/enableBTreeIndexing() removed, use defaultIndexType instead

- Remove duplicate findInsertionIndex method from BasicIndex - Add findInsertPositionInArray helper for simple arrays - Add deleteInSortedArray helper for deleting from sorted arrays - Keep findInsertPosition for tuple arrays (backward compatibility) - Update BasicIndex to use the new shared utility functions Co-authored-by: Kevin <[email protected]>

Replace three-iteration approach (spread, reverse, map) with a single backwards for loop for better performance. Co-authored-by: Kevin <[email protected]>

…zedIndex

… the failing unit test.

kevin-dp

I addressed my own review.

…Fe1MCKR6TXmrXaPSEXRx

KyleAMathews · 2026-01-19T16:52:00Z

/review

KyleAMathews · 2026-01-20T16:31:53Z

/review

claude · 2026-01-20T16:35:56Z

🔍 Comprehensive PR Review: Make Indexing Opt-In

PR: #950 | Branch: claude/estimate-bundle-without-indexing-01RpFe1MCKR6TXmrXaPSEXRx

This PR makes indexing opt-in for better tree-shaking, introduces a new @tanstack/db/indexing subpath export, and adds two index implementations: BasicIndex (read-optimized) and BTreeIndex (write-optimized).

📊 Summary

Category	Critical	Important	Suggestions
Code Quality	0	4	3
Tests	3	2	2
Error Handling	2	3	2
Type Design	0	2	4
Comments	2	4	3

🔴 Critical Issues (Must Fix)

1. Silent Failure in Index `remove()` Leaves Index Inconsistent

Files: read-optimized-index.ts:113-123, write-optimized-index.ts:101-111

The remove() method catches errors and returns early with only a console.warn, leaving the index in an inconsistent state:

remove(key: TKey, item: any): void {
  try {
    indexedValue = this.evaluateIndexExpression(item)
  } catch (error) {
    console.warn(`Failed to evaluate...`)
    return  // ⚠️ indexedKeys.delete(key) is NEVER called!
  }
  // ...
  this.indexedKeys.delete(key)  // This line never executes on error
}

Impact: Index corruption over time. Queries return stale/phantom data. Debugging is extremely difficult.

Fix: Either throw the error (preferred) or still call this.indexedKeys.delete(key) to maintain consistency.

2. Missing Tests for `ReadOptimizedIndex` (BasicIndex)

File: packages/db/src/indexes/read-optimized-index.ts

The ReadOptimizedIndex class (458 lines, exported as BasicIndex) has zero dedicated test coverage. All tests use WriteOptimizedIndex exclusively.

What could break undetected:

Range queries (gt, gte, lt, lte) edge cases
take() and takeReversed() pagination
Binary search bugs in findInsertPositionInArray
Memory leaks when removing values from sorted array

3. Missing Tests for Dev Mode Utilities

File: packages/db/src/indexes/index-registry.ts

The new dev mode utilities are completely untested:

configureIndexDevMode()
trackQuery()
checkCollectionSizeForIndex()
emitIndexSuggestion()

4. Missing Error Handling Test for `createIndex()` Without Index Type

When createIndex() is called without indexType and no defaultIndexType is set, an error should be thrown. This breaking change behavior is not tested.

🟠 Important Issues (Should Fix)

1. Config Mismatch: `autoIndex: 'eager'` Without `defaultIndexType` Fails Silently

File: auto-index.ts:17-28

When a user sets autoIndex: 'eager' but forgets defaultIndexType, auto-indexing is silently disabled with only a dev-mode warning. In production, there's no warning at all.

if (!collection.config.defaultIndexType) {
  if (isDevModeEnabled()) {  // Only warns in dev mode!
    console.warn(`Auto-indexing is disabled...`)
  }
  return false  // Silent in production
}

Recommendation: Throw at collection creation time if autoIndex: 'eager' is set without defaultIndexType.

2. Naming Inconsistency Between Internal and Public API

File: indexing.ts:27-36

Confusing name mapping:

BasicIndex → internally ReadOptimizedIndex
BTreeIndex → internally WriteOptimizedIndex

Error messages use internal names, causing confusion:

throw new Error(`Operation ${operation} not supported by BasicIndex`)  // But class is ReadOptimizedIndex

3. `equalityLookup()` Returns Internal Set Reference

Files: read-optimized-index.ts:241-244, write-optimized-index.ts

equalityLookup(value: any): Set<TKey> {
  return this.valueMap.get(normalizedValue) ?? new Set()  // Returns internal reference!
}

Callers can mutate the internal index state. Return a new Set instead.

4. Dev Mode Enabled by Default Can Cause Unexpected Console Warnings

File: index-registry.ts:8-13

Users who intentionally chose not to use indexes will see noisy console warnings about index suggestions.

5. Auto-Index Creation Failures Silently Swallowed

File: auto-index.ts:73-93

try {
  collection.createIndex(...)
} catch (error) {
  console.warn(`Failed to create auto-index...`)
  // Continues as if nothing happened
}

User expects indexes but queries silently fall back to full scans.

🟡 Suggestions (Nice to Have)

Type Design

IndexSuggestion: Use proper discriminated union to correlate optional fields with type:

export type IndexSuggestion =
  | { type: 'collection-size'; collectionSize: number; ... }
  | { type: 'slow-query'; queryTimeMs: number; queryCount: number; ... }

RangeQueryOptions: Consider generic type parameter for type-safe boundaries instead of any
getIndexDevModeConfig(): Return frozen copy to prevent external mutation

Code Comments

Update class docs to explain the name aliasing (ReadOptimizedIndex exported as BasicIndex)
Add concrete thresholds to help developers choose between index types
Document trackQuery() is called internally - most developers don't need it

Code Simplification

Significant duplicate code between ReadOptimizedIndex and WriteOptimizedIndex could be extracted to BaseIndex
queryPatterns Map in index-registry.ts grows unbounded - potential memory leak in long-running apps

✅ Strengths

Excellent tree-shaking setup - vite.config.ts and package.json exports are correctly configured
Simplified API - Removing async IndexResolver and LazyIndexWrapper reduces complexity significantly
Great changeset documentation - Clear migration paths with code examples
Well-documented entry point - indexing.ts module docs show all three usage patterns
Tests properly updated - All tests now explicitly pass defaultIndexType: WriteOptimizedIndex

📋 Recommended Action Plan

Before Merge (Critical)

Fix remove() method error handling in both index implementations
Add dedicated tests for ReadOptimizedIndex
Add tests for dev mode utilities

Before Merge (Important)

Throw error at collection creation if autoIndex: 'eager' without defaultIndexType
Fix naming inconsistency in error messages

Post-Merge

Consider type design improvements
Extract duplicate code to BaseIndex
Add memory management for query patterns tracking

🤖 Generated by multi-agent PR review

Researched JavaScript full-text search libraries that could integrate with TanStack DB's indexing architecture following PR #950's opt-in pattern. Key findings: - Orama recommended (2KB, used by tanstack.com, full features) - MiniSearch as alternative (7KB, class-based API) - FlexSearch for high-performance needs - Custom inverted index for minimal bundle Includes implementation approach and bundle size comparison.

kevin-dp requested changes Dec 11, 2025

View reviewed changes

kevin-dp force-pushed the claude/estimate-bundle-without-indexing-01RpFe1MCKR6TXmrXaPSEXRx branch from 6df29a2 to 79db466 Compare December 11, 2025 11:02

KyleAMathews added this to TanStack DB 1.0.0 release Jan 6, 2026

KyleAMathews moved this to Todo in TanStack DB 1.0.0 release Jan 6, 2026

KyleAMathews moved this from Todo to In Progress in TanStack DB 1.0.0 release Jan 7, 2026

KyleAMathews assigned kevin-dp Jan 7, 2026

claude and others added 11 commits January 12, 2026 10:27

chore: increase collectionSizeThreshold to 1000

2c14793

Most collections won't have perf issues until much larger sizes. Slow query detection (10ms) is the more actionable metric.

chore: add changeset for optional indexing

e824c74

fix: changeset should be minor (pre-1.0)

c22c170

docs: clarify MapIndex falls back to scanning for range queries

48a4398

Remove lazy-index file which re-appeared after rebase

647833e

Fix merge conflicts that escaped rebasing

b746aef

ci: apply automated fixes

ddcb1d7

kevin-dp force-pushed the claude/estimate-bundle-without-indexing-01RpFe1MCKR6TXmrXaPSEXRx branch from feaba11 to ddcb1d7 Compare January 12, 2026 09:33

autofix-ci bot and others added 3 commits January 12, 2026 09:34

ci: apply automated fixes (attempt 2/3)

26c8622

refactor(db): optimize orderedEntriesArrayReversed to use single pass

50a5fa2

Replace three-iteration approach (spread, reverse, map) with a single backwards for loop for better performance. Co-authored-by: Kevin <[email protected]>

github-actions bot force-pushed the claude/estimate-bundle-without-indexing-01RpFe1MCKR6TXmrXaPSEXRx branch from fe9b441 to 50a5fa2 Compare January 12, 2026 10:41

kevin-dp and others added 4 commits January 12, 2026 11:48

Simplify equalityLookup

e44fc72

ci: apply automated fixes

56230ac

Rename BasicIndex to ReadOptimizedIndex and BTreeIndex to WriteOptimi…

99bea20

…zedIndex

Improved warning

f91b250

kevin-dp and others added 3 commits January 12, 2026 12:22

Fix rangeQueryReversed for ReadOptimizedIndex

4e9e770

ci: apply automated fixes

ca03120

Fix problem with pagination when indexes aren't available. This fixes…

c2239d8

… the failing unit test.

kevin-dp marked this pull request as ready for review January 12, 2026 13:19

kevin-dp approved these changes Jan 12, 2026

View reviewed changes

Renamed indexes in changeset

a758237

kevin-dp moved this from In Progress to Ready for review in TanStack DB 1.0.0 release Jan 13, 2026

Merge branch 'main' into claude/estimate-bundle-without-indexing-01Rp…

f2796da

…Fe1MCKR6TXmrXaPSEXRx

Make indexing opt-in #950

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claude bot commented Jan 20, 2026

🔍 Comprehensive PR Review: Make Indexing Opt-In

📊 Summary

🔴 Critical Issues (Must Fix)

1. Silent Failure in Index remove() Leaves Index Inconsistent

2. Missing Tests for ReadOptimizedIndex (BasicIndex)

3. Missing Tests for Dev Mode Utilities

4. Missing Error Handling Test for createIndex() Without Index Type

🟠 Important Issues (Should Fix)

1. Config Mismatch: autoIndex: 'eager' Without defaultIndexType Fails Silently

2. Naming Inconsistency Between Internal and Public API

3. equalityLookup() Returns Internal Set Reference

4. Dev Mode Enabled by Default Can Cause Unexpected Console Warnings

5. Auto-Index Creation Failures Silently Swallowed

🟡 Suggestions (Nice to Have)

Type Design

Code Comments

Code Simplification

✅ Strengths

📋 Recommended Action Plan

Before Merge (Critical)

Before Merge (Important)

Post-Merge

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1. Silent Failure in Index `remove()` Leaves Index Inconsistent

2. Missing Tests for `ReadOptimizedIndex` (BasicIndex)

4. Missing Error Handling Test for `createIndex()` Without Index Type

1. Config Mismatch: `autoIndex: 'eager'` Without `defaultIndexType` Fails Silently

3. `equalityLookup()` Returns Internal Set Reference