Add warning for preload on on-demand collections

[KyleAMathews]

Calling .preload() on a collection with syncMode "on-demand" is a no-op since data is only loaded when queries request it. This change adds a warning to help users understand this behavior and suggests creating a live query instead.

The warning includes a link to the Query-Driven Sync blog post for additional context and guidance.

🎯 Changes

✅ Checklist

• I have followed the steps in the Contributing guide.
• I have tested this code locally with pnpm test:pr.

🚀 Release Impact

• This change affects published code, and I have generated a changeset.
• This change is docs/CI/dev-only (no release).

[changeset-bot]

🦋 Changeset detected

Latest commit: b679eda

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

This PR includes changesets to release 11 packages

Name	Type
@tanstack/db	Patch
@tanstack/angular-db	Patch
@tanstack/db-collection-e2e	Patch
@tanstack/electric-db-collection	Patch
@tanstack/powersync-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

[KyleAMathews]

"no-op" might be a bit strong — but generally speaking it's correct as .preload() isn't going to get their data loaded

[pkg-pr-new]

More templates

• todos
• tanstack-start-example-basic
• @tanstack/db-example-paced-mutations-demo
• tanstack-start-db-projects-example
• @tanstack/db-example-react-todo
• @tanstack/db-example-solid-todo

@tanstack/angular-db

npm i https://pkg.pr.new/@tanstack/angular-db@871

@tanstack/db

npm i https://pkg.pr.new/@tanstack/db@871

@tanstack/db-ivm

npm i https://pkg.pr.new/@tanstack/db-ivm@871

@tanstack/electric-db-collection

npm i https://pkg.pr.new/@tanstack/electric-db-collection@871

@tanstack/offline-transactions

npm i https://pkg.pr.new/@tanstack/offline-transactions@871

@tanstack/powersync-db-collection

npm i https://pkg.pr.new/@tanstack/powersync-db-collection@871

@tanstack/query-db-collection

npm i https://pkg.pr.new/@tanstack/query-db-collection@871

@tanstack/react-db

npm i https://pkg.pr.new/@tanstack/react-db@871

@tanstack/rxdb-db-collection

npm i https://pkg.pr.new/@tanstack/rxdb-db-collection@871

@tanstack/solid-db

npm i https://pkg.pr.new/@tanstack/solid-db@871

@tanstack/svelte-db

npm i https://pkg.pr.new/@tanstack/svelte-db@871

@tanstack/trailbase-db-collection

npm i https://pkg.pr.new/@tanstack/trailbase-db-collection@871

@tanstack/vue-db

npm i https://pkg.pr.new/@tanstack/vue-db@871

commit: b679eda

[github-actions]

Size Change: +174 B (+0.2%)

Total Size: 85.9 kB

Filename	Size	Change
./packages/db/dist/esm/collection/sync.js	2.29 kB	+174 B (+8.22%)	🔍

ℹ️ View Unchanged

Filename	Size
./packages/db/dist/esm/collection/change-events.js	1.38 kB
./packages/db/dist/esm/collection/changes.js	977 B
./packages/db/dist/esm/collection/events.js	388 B
./packages/db/dist/esm/collection/index.js	3.24 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	2.26 kB
./packages/db/dist/esm/collection/state.js	3.43 kB
./packages/db/dist/esm/collection/subscription.js	2.42 kB
./packages/db/dist/esm/deferred.js	207 B
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./packages/db/dist/esm/event-emitter.js	748 B
./packages/db/dist/esm/index.js	2.63 kB
./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	1.87 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	3.22 kB
./packages/db/dist/esm/query/builder/functions.js	733 B
./packages/db/dist/esm/query/builder/index.js	3.84 kB
./packages/db/dist/esm/query/builder/ref-proxy.js	917 B
./packages/db/dist/esm/query/compiler/evaluators.js	1.35 kB
./packages/db/dist/esm/query/compiler/expressions.js	430 B
./packages/db/dist/esm/query/compiler/group-by.js	1.8 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	1.25 kB
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./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	5.26 kB
./packages/db/dist/esm/query/live/collection-registry.js	264 B
./packages/db/dist/esm/query/live/collection-subscriber.js	1.74 kB
./packages/db/dist/esm/query/live/internal.js	130 B
./packages/db/dist/esm/query/optimizer.js	2.56 kB
./packages/db/dist/esm/query/predicate-utils.js	2.88 kB
./packages/db/dist/esm/query/subset-dedupe.js	921 B
./packages/db/dist/esm/scheduler.js	1.21 kB
./packages/db/dist/esm/SortedMap.js	1.18 kB
./packages/db/dist/esm/strategies/debounceStrategy.js	237 B
./packages/db/dist/esm/strategies/queueStrategy.js	422 B
./packages/db/dist/esm/strategies/throttleStrategy.js	236 B
./packages/db/dist/esm/transactions.js	2.9 kB
./packages/db/dist/esm/utils.js	881 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/index-optimization.js	1.51 kB
./packages/db/dist/esm/utils/type-guards.js	157 B

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

[github-actions]

Size Change: 0 B

Total Size: 3.34 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	1.11 kB
./packages/react-db/dist/esm/useLiveSuspenseQuery.js	431 B
./packages/react-db/dist/esm/usePacedMutations.js	401 B

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

[samwillis]

Great addition!