chroma-core/chroma · error · InvalidDimensionException

InvalidDimension

InvalidDimension

Error message

Dimensionality of ({dim}) does not match indexdimensionality ({self._dimensionality})

What it means

Error "Dimensionality of ({dim}) does not match indexdimensionality ({self._dimensionality})" thrown in chroma-core/chroma.

Source

Thrown at chromadb/segment/impl/vector/local_hnsw.py:230

            max_elements=DEFAULT_CAPACITY,
            ef_construction=self._params.construction_ef,
            M=self._params.M,
        )
        index.set_ef(self._params.search_ef)
        index.set_num_threads(self._params.num_threads)

        self._index = index
        self._dimensionality = dimensionality

    @trace_method("LocalHnswSegment._ensure_index", OpenTelemetryGranularity.ALL)
    def _ensure_index(self, n: int, dim: int) -> None:
        """Create or resize the index as necessary to accomodate N new records"""
        if not self._index:
            self._dimensionality = dim
            self._init_index(dim)
        else:
            if dim != self._dimensionality:
                raise InvalidDimensionException(
                    f"Dimensionality of ({dim}) does not match index"
                    + f"dimensionality ({self._dimensionality})"
                )

        index = cast(hnswlib.Index, self._index)

        if (self._total_elements_added + n) > index.get_max_elements():
            new_size = int(
                (self._total_elements_added + n) * self._params.resize_factor
            )
            index.resize_index(max(new_size, DEFAULT_CAPACITY))

    @trace_method("LocalHnswSegment._apply_batch", OpenTelemetryGranularity.ALL)
    def _apply_batch(self, batch: Batch) -> None:
        """Apply a batch of changes, as atomically as possible."""
        deleted_ids = batch.get_deleted_ids()
        written_ids = batch.get_written_ids()
        vectors_to_write = batch.get_written_vectors(written_ids)

View on GitHub (pinned to aecdd12c8a)

When it happens

Trigger: Thrown at chromadb/segment/impl/vector/local_hnsw.py:230 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of chroma-core/chroma@aecdd12c8a (2026-08-16). Data as JSON: /api/errors/81419841e2e1e4e7. Report an issue: GitHub.