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fix(db)!: keep Collection keys in the key type and merge large sync restores - #2266
This PR makes every Collection key a string or a number, as the key type declares. It also makes large sync publications faster and makes the bundle smaller. A typical app is 56 bytes smaller after gzip. The work started as an evaluation of ideas from turbopuffer's fully vectorized search engine post. This PR keeps only the changes that gave a net improvement.
Grouped keys now match the key type
A Collection key has the type string | number. But a grouped live query used the raw group value as the key when it grouped by one field. Grouping by a nullable field is a valid query, so the null group got the key null:
Boolean and bigint group values had the same problem. These keys are outside the declared type, so typed code could not read the group with get(). Code that sorts keys could also fail. SortedMap used compareKeys, which gives compareKeys(null, 5) and compareKeys(5, null) the same result. Ordered reads could then put rows in the wrong position or skip them.
The maintainer decided that the producer must match the type. The type does not widen. Now a null, undefined, boolean, or bigint group value gets a string key in the namespace that normalizeValue reserves for internal encodings. A string group value cannot occupy that namespace, so the key cannot collide with a group whose value is the string "null". String and number group values keep their keys. The row's own field still holds null, and $key holds the new key.
sync.write now rejects a key that is not a string or a number with UndefinedKeyError or InvalidKeyError. Optimistic mutations already used this check, and both paths now share one function. A sync adapter whose getKey returns a bad key fails at the boundary, before the key reaches ordered state. For a bigint key, the development message now shows the key. Before, JSON.stringify failed with a TypeError.
With all keys in the key type, SortedMap uses compareKeys directly. This PR deletes the runtimeKeyCount fallback from main, and it adds no nullish key order.
Large publications merge instead of sort
When one publication applies 512 or more sync operations, SortedMap defers ordering until the end of the batch. Before, the restore sorted every key again. Now the keys written during the batch leave the order by Set membership. The restore then sorts those keys that are still in the map and merges them into the order in one pass. This takes O(n + k log n) time for k changed keys.
These are the results of a load benchmark with 50,000 rows and a compare option:
Operations in each sync transaction
main
This PR
100
382 ms
324 ms
600
1,734 ms
187 ms
5,000
310 ms
147 ms
Batches below 512 operations use the immediate path, as before. Some details of the restore:
The merge writes the result into the existing key array. A key iterator that is open before the restore reads the restored order, as on main.
A sync source can change a row object in place and write it again. Binary search can then miss the old position of the row. The immediate path finds that position with a scan, so it does not delete a neighbor.
Scope of the SortedMap contract
SortedMap now promises only the behavior that Collection state uses. It does not promise full Map behavior. This is a maintainer decision. The promised behavior is:
Setting, deleting, and clearing work as in a Map for Collection keys. A NaN key is one key, after every other number. A grouped query uses it for a NaN group.
Views show the rows in key order or in compare order, with key order to break ties.
A row that changes in place before the restore sorts by its current value. After a placed row changes in place, the order can be wrong, but each key stays in the views one time with its current value.
Deferred deletes during iteration yield each row of the starting order one time. overlayActiveTransactions depends on this when it deletes settled transactions.
A restore has a limit on comparator calls. For k deferred keys among n other keys, the limit is k × (⌈log₂ k⌉ + ⌈log₂(n + 1)⌉ + 2). An ordered read with no deferred keys makes no calls.
This PR does not promise:
the result of immediate writes or clear() during iteration
the order of rows after a placed row changes in place without a write
keys outside the key type, or -0 keys
the state after the comparator throws an error
The coverage map records these limits. This PR also deletes the unused forEach method and the public SortedMap export. These are breaking changes, but they are acceptable because they are part of the rc1 release.
Other changes
These two changes are independent of the key and SortedMap work.
Keyed MultiSet.consolidate (@tanstack/db-ivm): the function now groups entries in nested maps by key and value. It no longer builds a string for each value. This PR deletes getStringId, which the package did not export. The existing MultiSet consolidation oracle covers this change.
Collection commit loop: the loop no longer builds the syncedInsertedOrUpdatedKeys set, which no code read. Inserts now skip the virtual-prop snapshots that only deletes and updates use.
This PR also adds a named replay to load-subset-replay-refinement-oracle.test.ts. The replay is the trace from #2224, a failed include demand during a marker replay. #2229 fixed that defect. I closed#2224 as fixed and #2239 as a duplicate.
Oracle evidence
The review record gives the outcome for each rubric requirement and the full review ledger.
Grouped result keys
Law: a grouped live-query Collection gives each group one key of the Collection key type. Two groups never share a key, and a group that stays after a change keeps its key. Authority: the TKey constraint, the existing InvalidKeyError for mutations, and the maintainer decision.
Grammar: histories move, delete, and insert rows. The group values are:
strings, numbers, and NaN
null, undefined, booleans, and a bigint
strings that print like those values, such as "null" and "true"
strings in the reserved namespace
Reach: each state needs at least 5 of the 80 histories in a campaign. The counts are:
a nullish group: 32 to 38
a group beside a string that prints like it: 18 to 21
a key that stays across a change: 49 to 53
RED: on the parent commit, all 5 tests fail with the keys undefined, null, false, and 10n.
GREEN: 5 of 5 pass.
Mutants: an encoding with String(value) fails because lookalike keys collide. An encoding of nullish values only fails because boolean keys stay. An encoding of only the internal D2 key is equivalent in this domain, because the Collection uses the public group key. So the fix changes only the public key.
Boundary witness: a focused test shows that sync.write rejects undefined, null, boolean, and bigint keys before it stages them. All 4 cases fail on the parent commit.
Limits: Dates, -0, objects, and multi-field groups are outside this owner. The aggregate select oracle owns grouped values.
SortedMap
Grammar: the model stores numbers, and production stores row objects. The actions are:
deferred and immediate sets and deletes, and clear()
bursts of 17 to 41 deferred keys
prunes during iteration
in-place changes of a deferred row or a placed row
Reach: each state needs at least 5 of the 100 histories in a campaign. The lowest counts in two local runs are:
a placed NaN key that an action writes without deferral: 7
a restore whose limit is below n: 19
a changed placed row that a later action writes: 11
a deferred row that changes before the restore: 11
a burst restore, and a row that a prune yields after it deleted a row: more than 30
GREEN: 7 of 7 oracle tests and 21 of 21 supplemental examples pass.
Mutants: the oracle rejects each of these mutants:
Mutant
Result
Sorts all keys again at each restore
108 comparator calls against a bound of 7
Sorts the kept keys with the changed keys added at the end
34 calls against a bound of 7
Sorts again when the map has no deferred key
calls on a clean read
Deletes the scan for a row that changed in place
wrong neighbor deleted
Compares slots with ===
a placed NaN key deletes the last key
Keeps the old positions of changed keys
order mismatch
Applies deferred deletes immediately
prune skips a row
Places a deferred row by its value at the write
order mismatch
Before this change, a mutant that sorted all keys again passed all 30 oracle tests. The work law closes that gap.
A regression inside this PR: an earlier commit compared slots with ===. With comparator order, a write to a placed NaN key then deleted the last key. main did not have this defect. The oracle now generates NaN keys. It failed on that commit and passes now.
Limits: the work law applies only with a comparator, because the public API cannot observe the work of key order.
Code weight
pnpm size:compare against the merge-base b8d8ee07c gives these production results in bytes:
Target
Δ gzip
Δ brotli
app
−56
+9
app-effect
−41
−11
app-group-by
−38
−18
app-includes
−60
+56
app-join
−61
−64
app-local-storage
−42
−59
app-optimistic-action
−53
+26
app-paced-mutations
−47
+36
@tanstack/db package bundle
−2
−67
Gzip is smaller in every scenario. Brotli results for these small differences are not consistent.
Verification
The local machine had a high load, so I ran only focused suites. CI runs the full suite.
The new and changed oracles pass: grouped result keys 5 of 5, SortedMap 7 of 7, and the supplemental SortedMap examples 21 of 21.
These suites pass: collection (179), group-by (172), transactions, collection-truncate, group-by-work, aggregate-select-oracle, includes, includes-space-oracle, live-query-collection, collection-mutation-startup-oracle, bucket-facade-rollback-oracle, and load-subset-replay-refinement-oracle.
The type check, eslint, and the mangle-cache check pass. assertCollectionKey is internal, not part of the public API.
Some fast-check oracles did not load locally, with the error "Vitest failed to find the current suite". These are pooled-live-query-oracle, includes-oracle, includes-collection-oracle, includes-cross-formulation-oracle, and includes-temporal-oracle. The same error occurs with main. The probable cause is the borrowed node_modules directory. CI runs them.
This pull request and its description were written by Isaac.
- SortedMap orders runtime undefined/null keys first, so binary search finds
them; this removes the runtimeKeyCount immediate-path fallback.
- Deferred restore removes dirty keys by membership and merges the sorted
dirty keys in one pass (O(n + k log n)) instead of re-sorting every key.
- Remove SortedMap's unused forEach and its public export.
- Keyed MultiSet.consolidate uses nested Maps instead of string ids.
- Collection commit loop drops a never-read set and computes virtual props
only for deletes and updates.
- Add a named load-subset replay for the failed include demand trace.
Co-authored-by: Isaac <no-reply@databricks.com>
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The changes revise SortedMap ordering and exports, collection key validation, grouped-query result keys, and keyed MultiSet consolidation. They also update Collection sync event generation and add oracle and unit test coverage for these behaviors.
Collection mutations and sync writes validate keys as strings or numbers. Development error messages serialize bigint values safely. Tests cover rejected sync writes for undefined, null, boolean, and bigint keys.
Grouped queries normalize primitive group identities other than strings and numbers. Tests check result key types, uniqueness, and stability across changes. Documentation describes the string-or-number key rule.
Ordered collection views
Layer / File(s)
Summary
SortedMap ordering and restoration packages/db/src/SortedMap.ts, packages/db/mangle-cache.json, packages/db/tests/SortedMap-oracle.test.ts, packages/db/tests/SortedMap.test.ts
SortedMap tracks deferred writes and deletes by dirty key, removes old slots, and merges restored keys into retained order. Iterators obtain ordering through keys(). Tests cover deferred changes, ordering, and Collection sync.
Sync event generation and public references packages/db/src/collection/state.ts, packages/db/tests/SortedMap.test.ts, packages/db/tests/query/bucket-facade-rollback-oracle.property.test.ts, packages/db/tests/SortedMap-oracle.test.ts, docs/contributing/oracle-coverage.md, docs/contributing/oracle-reviews/pr-2266-collection-key-type.md, packages/db/src/index.ts, docs/reference/classes/SortedMap.md, docs/reference/index.md, .changeset/sortedmap-merge-restore.md
Sync event generation handles absent previous or next values. The SortedMap export and reference page are removed. Oracle coverage and release notes describe the related changes.
Keyed MultiSet consolidation
Layer / File(s)
Summary
Nested-map grouping for keyed records packages/db-ivm/src/multiset.ts, packages/db-ivm/src/utils.ts
Keyed records use nested Maps to group leaf and tuple values, sum multiplicities, and remove zero totals. The getStringId helper is removed.
Ordered-replay oracle history
Layer / File(s)
Summary
Marker-replay failure case packages/db/tests/query/load-subset-replay-refinement-oracle.test.ts
The oracle adds a named history for a failed load during on-demand marker replay with includes enabled and no joined source.
TanStack/db#2264: The PR adds executable SortedMap and grouped-key oracle coverage, but does not restore the specific files listed in the issue.
TanStack/db#2234: The PR adds executable oracle coverage, but does not implement the lint rules or CI checks described in the issue.
Possibly related PRs
TanStack/db#2262: Both PRs change Collection sync transaction processing and publication behavior, including insert, update, and delete handling.
Suggested reviewers:kevin-dp
Merge Risk: Low · previous review ea4cf
Some grouped-row lookups may fail if readers rely on the guide’s unqualified key rule. Clarify the exceptions; the remaining risk is bounded and does not block merging.
Pre-merge checks: 4 · 1
Failed checks: 1 warning
Check name
Status
Explanation
Resolution
Docstring Coverage
Docstring coverage is 56.25% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Documentation-only edits and deletions within surv…
Write docstrings for the functions missing them to satisfy the coverage threshold.
Passed checks: 4 passed
Check name
Status
Explanation
Title check
The title names the two main changes: Collection keys are kept in the declared key type (string | number), and large sync restores are merged. Both match the raw summary and the PR objectives. The tit…
Linked Issues check
The only directly linked issue is #2224. It is closed and marked as historical context only. No active directly linked target remains, so no linked-issue coding requirement applies. The named replay i…
Out of Scope Changes check
The changed files map to the stated PR scope: grouped key encoding and validation; SortedMap restore behavior, contract, tests, and documentation; keyed MultiSet consolidation; the Collection commit l…
Description check
The description clearly explains the changes, motivation, oracle coverage, test evidence, known limitations, and release impact. It does not reproduce the required Checklist and Release Impact heading…
Full details: Title check
Explanation
The title names the two main changes: Collection keys are kept in the declared key type (string | number), and large sync restores are merged. Both match the raw summary and the PR objectives. The title uses the conventional commit form with a breaking-change marker, which fits the removed public SortedMap export and forEach method. It is somewhat long at 76 characters, but it is specific and accurate.
Full details: Linked Issues check
Explanation
The only directly linked issue is #2224. It is closed and marked as historical context only. No active directly linked target remains, so no linked-issue coding requirement applies. The named replay is supporting test coverage for the PR scope and is not required by the closed issue.
Full details: Out of Scope Changes check
Explanation
The changed files map to the stated PR scope: grouped key encoding and validation; SortedMap restore behavior, contract, tests, and documentation; keyed MultiSet consolidation; the Collection commit loop; the named replay; oracle registration and coverage records; release metadata; and required test instrumentation and mangle-cache updates. The changeset and documentation support these code changes. No unrelated change is demonstrated by the whole-PR summary.
Full details: Description check
Explanation
The description clearly explains the changes, motivation, oracle coverage, test evidence, known limitations, and release impact. It does not reproduce the required Checklist and Release Impact headings or the exact pnpm test checkbox, but it provides equivalent verification details and documents the changeset and focused test results.
Full details: Docstring Coverage
Explanation
Docstring coverage is 56.25% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 16 functions across 17 files. (3 skipped: 3 unsupported.)
Resolution
Write docstrings for the functions missing them to satisfy the coverage threshold.
Finishing Touches: 💡 1
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Comparing 2ff693211 (this PR) against 7e46f81ad (base). Write times are per-write medians over 100 iterations (20 warmup writes). Cold hydrate is one timed first load of each query.
Overall median write time vs base: 0.96× · cold hydrate time: 1.02× (geometric mean of per-case ratios; lower is faster).
Writes: 2 regression(s), 3 improvement(s) (threshold: ±20% and >0.05ms).
Cold hydrate: 2 regression(s), 0 improvement(s) (threshold: ±50% and >5ms).
Per-case flags are noisy on shared runners. Read the geometric means first.
Writes
Query
Δ median write time (geomean)
Best case
Worst case
Flags
list: newest 50 open
-1.8%
-32.1%
+64.7%
1 🟢
list + author
+7.8%
-8.7%
+129.4%
1 🔴
list + comment count
-3.5%
-18.8%
+18.3%
—
list + 3 recent comments
-10.5%
-55.6%
+75.1%
1 🔴 1 🟢
issue detail + comments
-12.5%
-50.3%
+12.6%
1 🟢
Cold hydrate
Query
Δ cold hydrate time (geomean)
Best case
Worst case
Flags
list: newest 50 open
+5.9%
-29.2%
+548.4%
1 🔴
list + author
-3.8%
-21.6%
+38.3%
—
list + comment count
+3.7%
-25.9%
+109.5%
—
list + 3 recent comments
-2.0%
-40.3%
+68.2%
1 🔴
issue detail + comments
+0.7%
-22.9%
+65.7%
—
Each row aggregates the 14.4 scale/index/write-mode configurations of that query; per-configuration tables below.
Runner: node v24.8.0, linux 6.17.0-1022-azure, INTEL(R) XEON(R) PLATINUM 8573C. Timings on shared CI runners are noisy; treat small deltas as indicative only.
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Actionable comments posted: 1
🪄 Fix comments: Fix CodeRabbit comments on this PR
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Inline comments:
Review comments at @packages/db/src/SortedMap.ts:
- Line 145: Update the miss check in SortedMap’s unplace method to check whether
the binary-search index is at or beyond sortedKeys.length before comparing the
indexed key. When out of bounds or the key does not match, run the existing
indexOf fallback so runtime undefined keys are removed correctly.
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Minor · Functional Correctness · Quick win
Fix the miss check in unplace for a runtime undefined key.
When a comparator value is mutated in place, the binary search can return sortedKeys.length. For an undefined key, sortedKeys[sortedKeys.length] is also undefined. The check !== key is then false, so the fallback scan does not run. splice(length, 1) removes nothing and the stale slot stays in sortedKeys. A later ordered read then yields that key with this.map.get(key)! returning undefined.
This case needs a runtime undefined key, a comparator, and a value mutated in place. unplace exists to handle in-place mutation, so it should also handle this key. Check the bound before the identity.
Proposed fix
--- "a/packages/db/src/SortedMap.ts"+++ "b/packages/db/src/SortedMap.ts"@@ -142,7 +142,8 @@
// Binary search misses a value that a sync source mutated in place after
// it was placed, so fall back to a scan.
let index = this.indexOf(key, this.map.get(key)!)
- if (this.sortedKeys[index] !== key) index = this.sortedKeys.indexOf(key)+ if (index >= this.sortedKeys.length || this.sortedKeys[index] !== key)+ index = this.sortedKeys.indexOf(key)
this.sortedKeys.splice(index, 1)
}
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Review comment at @packages/db/src/SortedMap.ts at line 145:
Update the miss check in SortedMap’s unplace method to check whether the
binary-search index is at or beyond sortedKeys.length before comparing the
indexed key. When out of bounds or the key does not match, run the existing
indexOf fallback so runtime undefined keys are removed correctly.
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- A single-field group whose value is null, undefined, a boolean, or a
bigint gets a string key in the reserved normalized-key namespace, so
grouped keys are always strings or numbers.
- sync.write rejects keys that are not strings or numbers with the same
check that mutations use; key error messages show bigints.
- SortedMap drops its nullish key order and wrapped sort and compares keys
with compareKeys.
- New grouped result key oracle; the SortedMap oracle adds in-place row
changes and a comparator-call work law for restores, and its example
tests move to SortedMap.test.ts.
Co-authored-by: Isaac <no-reply@databricks.com>
KyleAMathews
changed the title
perf(db): keep nullish keys in ordered state and merge large sync restores
fix(db)!: keep Collection keys in the key type and merge large sync restores
Oct 27, 2026
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Nitpick comments: 1
packages/db/tests/collection.test.ts: 1
1277-1315: Trivial · Maintainability & Code Quality · Heavy lift
Extend the contract-owning oracle for invalid sync keys.
sync.write now rejects non-string and non-number keys. The new unit test is only a focused witness for four invalid values. Extend the SortedMap oracle with this key-validation law and representative invalid-key cases. Assert that rejected writes have no effect on a later commit. If the sync boundary needs a separate receiving oracle, document that owner and the reason in docs/contributing/oracle-coverage.md.
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Review comment at @packages/db/tests/collection.test.ts around lines 1277 -
1315:
Extend the contract-owning SortedMap oracle to cover rejection of non-string and
non-number sync keys with representative invalid values, and assert rejected
writes do not affect a subsequent commit. Use the sync.write behavior in this
test as the reference; if validation belongs to a separate receiving oracle,
document that ownership and rationale in the oracle coverage guide.
Source: Learnings
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Nitpick comments:
Review comments at @packages/db/tests/collection.test.ts:
- Around line 1277-1315: Extend the contract-owning SortedMap oracle to cover
rejection of non-string and non-number sync keys with representative invalid
values, and assert rejected writes do not affect a subsequent commit. Use the
sync.write behavior in this test as the reference; if validation belongs to a
separate receiving oracle, document that ownership and rationale in the oracle
coverage guide.
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- SortedMap's slot check compares keys as Map does, so deleting or
rewriting a placed NaN key no longer removes the last key. The SortedMap
oracle now generates NaN keys and declares reach for a placed NaN write.
- Move assertCollectionKey to internal utils so it is not public API.
- The live-queries guide states that null, undefined, boolean, and bigint
group values get string keys, read from $key.
Co-authored-by: Isaac <no-reply@databricks.com>
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Actionable comments posted: 1
🪄 Fix comments: Fix CodeRabbit comments on this PR
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Review comments at @docs/guides/live-queries.md:
- Line 1699: Update the “Single column grouping” statement to limit the
direct-key guarantee to ordinary string or number values when using the default
key function; note that strings in the reserved `\u0000tanstack-db:` namespace
are normalized and a configured `getKey` can override the grouped-result key.
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docs/contributing/oracle-coverage.md
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> **Note**: Grouped results are keyed differently based on the grouping:
> - **Single column grouping**: Keyed by the actual value (e.g., `deptStats.get(1)`)
> - **Single column grouping**: A string or number group value is the key (e.g., `deptStats.get(1)`). A `null`, `undefined`, boolean, or bigint group value gets a string key instead, because Collection keys are strings or numbers. Read that key from the row's `$key`.
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Minor · Functional Correctness · Quick win
Qualify the direct-key guarantee.
String values in the reserved \u0000tanstack-db: namespace are normalized to a different key. A configured getKey also overrides the default grouped-result key. Therefore, this statement is not true for every string or number value. Document these exceptions or limit the statement to ordinary values with the default key function. (raw.githubusercontent.com)
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Review comment at @docs/guides/live-queries.md at line 1699:
Update the “Single column grouping” statement to limit the direct-key guarantee
to ordinary string or number values when using the default key function; note
that strings in the reserved `\u0000tanstack-db:` namespace are normalized and a
configured `getKey` can override the grouped-result key.
After applying the fix, consider running `coderabbit review --agent` for local
review. Visit https://docs.coderabbit.ai/cli?utm_source=ghpr
- Register group-result-key.groups in the replay manifest that main now
requires for every property.
- The guide note on grouped keys covers reserved-prefix strings and getKey.
- The review record appends the merge, the CodeRabbit item, and the
size:compare numbers.
Co-authored-by: Isaac <no-reply@databricks.com>
Brings in #2266 (Collection keys stay in the key type; large sync
restores merge) and #2103 (browser-sqlite loads its WASM as a separate
asset). The coverage map's two conflicting rows changed on one side
each; the mangle cache is regenerated. db, query-db, Electric, PowerSync,
TrailBase, both SQLite persistence packages, and React pass on the
merged tree.
Co-authored-by: Isaac <no-reply@databricks.com>
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This PR makes every Collection key a string or a number, as the key type declares. It also makes large sync publications faster and makes the bundle smaller. A typical app is 56 bytes smaller after gzip. The work started as an evaluation of ideas from turbopuffer's fully vectorized search engine post. This PR keeps only the changes that gave a net improvement.
Grouped keys now match the key type
A Collection key has the type
string | number. But a grouped live query used the raw group value as the key when it grouped by one field. Grouping by a nullable field is a valid query, so thenullgroup got the keynull:Boolean and bigint group values had the same problem. These keys are outside the declared type, so typed code could not read the group with
get(). Code that sorts keys could also fail.SortedMapusedcompareKeys, which givescompareKeys(null, 5)andcompareKeys(5, null)the same result. Ordered reads could then put rows in the wrong position or skip them.The maintainer decided that the producer must match the type. The type does not widen. Now a
null,undefined, boolean, or bigint group value gets a string key in the namespace thatnormalizeValuereserves for internal encodings. A string group value cannot occupy that namespace, so the key cannot collide with a group whose value is the string"null". String and number group values keep their keys. The row's own field still holdsnull, and$keyholds the new key.sync.writenow rejects a key that is not a string or a number withUndefinedKeyErrororInvalidKeyError. Optimistic mutations already used this check, and both paths now share one function. A sync adapter whosegetKeyreturns a bad key fails at the boundary, before the key reaches ordered state. For a bigint key, the development message now shows the key. Before,JSON.stringifyfailed with aTypeError.With all keys in the key type,
SortedMapusescompareKeysdirectly. This PR deletes theruntimeKeyCountfallback frommain, and it adds no nullish key order.Large publications merge instead of sort
When one publication applies 512 or more sync operations,
SortedMapdefers ordering until the end of the batch. Before, the restore sorted every key again. Now the keys written during the batch leave the order bySetmembership. The restore then sorts those keys that are still in the map and merges them into the order in one pass. This takes O(n + k log n) time for k changed keys.These are the results of a load benchmark with 50,000 rows and a
compareoption:mainBatches below 512 operations use the immediate path, as before. Some details of the restore:
main.Scope of the SortedMap contract
SortedMapnow promises only the behavior that Collection state uses. It does not promise fullMapbehavior. This is a maintainer decision. The promised behavior is:Mapfor Collection keys. ANaNkey is one key, after every other number. A grouped query uses it for aNaNgroup.compareorder, with key order to break ties.overlayActiveTransactionsdepends on this when it deletes settled transactions.This PR does not promise:
clear()during iteration-0keysThe coverage map records these limits. This PR also deletes the unused
forEachmethod and the publicSortedMapexport. These are breaking changes, but they are acceptable because they are part of the rc1 release.Other changes
These two changes are independent of the key and
SortedMapwork.MultiSet.consolidate(@tanstack/db-ivm): the function now groups entries in nested maps by key and value. It no longer builds a string for each value. This PR deletesgetStringId, which the package did not export. The existing MultiSet consolidation oracle covers this change.syncedInsertedOrUpdatedKeysset, which no code read. Inserts now skip the virtual-prop snapshots that only deletes and updates use.This PR also adds a named replay to
load-subset-replay-refinement-oracle.test.ts. The replay is the trace from #2224, a failed include demand during a marker replay. #2229 fixed that defect. I closed #2224 as fixed and #2239 as a duplicate.Oracle evidence
The review record gives the outcome for each rubric requirement and the full review ledger.
Grouped result keys
TKeyconstraint, the existingInvalidKeyErrorfor mutations, and the maintainer decision.NaNnull,undefined, booleans, and a bigint"null"and"true"undefined,null,false, and10n.String(value)fails because lookalike keys collide. An encoding of nullish values only fails because boolean keys stay. An encoding of only the internal D2 key is equivalent in this domain, because the Collection uses the public group key. So the fix changes only the public key.sync.writerejectsundefined,null, boolean, and bigint keys before it stages them. All 4 cases fail on the parent commit.-0, objects, and multi-field groups are outside this owner. The aggregate select oracle owns grouped values.SortedMap
clear()NaNkey that an action writes without deferral: 7===NaNkey deletes the last key===. With comparator order, a write to a placedNaNkey then deleted the last key.maindid not have this defect. The oracle now generatesNaNkeys. It failed on that commit and passes now.Code weight
pnpm size:compareagainst the merge-baseb8d8ee07cgives these production results in bytes:appapp-effectapp-group-byapp-includesapp-joinapp-local-storageapp-optimistic-actionapp-paced-mutations@tanstack/dbpackage bundleGzip is smaller in every scenario. Brotli results for these small differences are not consistent.
Verification
The local machine had a high load, so I ran only focused suites. CI runs the full suite.
SortedMap7 of 7, and the supplementalSortedMapexamples 21 of 21.collection(179),group-by(172),transactions,collection-truncate,group-by-work,aggregate-select-oracle,includes,includes-space-oracle,live-query-collection,collection-mutation-startup-oracle,bucket-facade-rollback-oracle, andload-subset-replay-refinement-oracle.assertCollectionKeyis internal, not part of the public API.pooled-live-query-oracle,includes-oracle,includes-collection-oracle,includes-cross-formulation-oracle, andincludes-temporal-oracle. The same error occurs withmain. The probable cause is the borrowednode_modulesdirectory. CI runs them.This pull request and its description were written by Isaac.