rxdb: count() is incorrect

In our web app, we do this:

const rxQuery = collection.count({
    selector: {
      id: {
        $eq: 'persistentStateBlob',
      },
    },
  });
const result = await.exec();

Expected: result is 0. Actual: result is 1.

In fact, if I use the following code instead…

const rxQuery = collection.find({
    selector: {
      id: {
        $eq: 'persistentStateBlob',
      },
    },
  });
const result = (await.exec()).length;

… result is 0. (That’s the exact same query)

Data

The collection does contain one item with an ID of persistentStateBlob2.

Schema

{
    primaryKey: 'id',
    properties: {
        id: { type: 'string', maxLength: 100 },
        value: { type: 'string' },
    },
    required: ['value'],
    type: 'object',
    version: 0,
}

Versions and storage

• rxdb: 14.11.1
• rxdb-premium: 14.11.1
• storage: premium IndexedDB storage via shared storage worker

What I’ve tried

### With our app

• Chromium and Firefox browsers.
• Disabling eventReduce.
• Disabling multiInstance.
• Removing the key compression plugin (this collection doesn’t use it anyway).
• Disabling the shared storage worker wrapper.
• Using the memory storage (without the shared storage worker).
• Deleting the IndexedDB databases in browser devtools.

All behave the same.

RxDB tests

• I created a test in test/unit/bug-report.test.ts and ran it with node+dexie; it passed.
• I changed the count matching only test in test/unit/rx-collection.test.ts and ran it with node+dexie; it passed.

Other notes

• count(...) (with a selector) correctly returns 0 if the collection is empty.
• count() without any argument seems correct.