Error with joins between progressive collections

[fcannizzaro]

• I've validated the bug against the latest version of DB packages

Describe the bug
If a LiveQuery uses a join with a collection that uses progressive syncMode this error happens (I tested using electric collections)

Uncaught (in promise) Error: Snapshot requests are not supported in full mode, as the consumer is guaranteed to observe all data
    at ShapeStream.<anonymous> (index.mjs:966:15)
    at Generator.next (<anonymous>)
    at index.mjs:65:61
    at new Promise (<anonymous>)
    at __async (index.mjs:49:10)
    at ShapeStream.requestSnapshot (index.mjs:964:12)
    at DeduplicatedLoadSubset.loadSubset [as _loadSubset] (electric.js:312:24)
    at DeduplicatedLoadSubset.loadSubset [as syncLoadSubsetFn] (subset-dedupe.js:41:34)
    at CollectionSyncManager.loadSubset (sync.js:203:27)
    at CollectionSubscription.requestSnapshot (subscription.js:113:46)

Also switching the syncMode to on-demand fixes the error (I think it loads all the joined collections cause I do not see any subset param sent in the request).

To Reproduce
Just a useLiveQuery with a join between collections with syncMode: progressive

[am1006]

I've also observed this behaviour when using useLiveSuspenseQuery:

  const { data: messages } = useLiveSuspenseQuery((q) =>
    q
      .from({ message: messagesCollection })
      .orderBy(({ message }) => message.created_at, "desc"),
  );

[kevin-dp]

/reproduce

[claude]

Investigation Summary

I investigated this issue and created comprehensive tests to reproduce the scenarios described. Here's what I found:

Analysis

The error "Snapshot requests are not supported in full mode" occurs when requestSnapshot() is called on a ShapeStream that's in full mode. For progressive mode collections:

• During the buffering phase: uses fetchSnapshot() ✓
• After initial sync completes: returns early without calling requestSnapshot() ✓

Looking at the timeline:

• This issue was created on Nov 13, 2025
• PR fix electric collection progressive mode #852 "fix electric collection progressive mode" was merged on Nov 21, 2025
• PR fix electric collection progressive mode #852 specifically fixed progressive mode to use fetchSnapshot() during buffering and avoid requestSnapshot() entirely after initial sync

Test Results

I created tests covering:

1. Joins between two progressive collections after initial sync
2. Joins when the joined collection is still in buffering phase
3. Ordered queries on progressive collections (from the comment by @am1006)
4. Ordered queries with limit

All tests pass, confirming the current code handles these scenarios correctly without calling requestSnapshot().

Conclusion

This issue appears to have been already fixed by PR #852 (released in v0.2.4, current version is v0.2.31).

If you're still experiencing this issue, please verify you're using @tanstack/electric-db-collection version 0.2.4 or later. If you can still reproduce with the latest version, please provide:

• Exact package versions
• Minimal reproduction code
• Full error stack trace

PR

I've submitted #1232 which adds regression tests to ensure this scenario stays covered.

[kevin-dp]

Closing this issue as it appears to be solved.