dgraph-io/dgraph · error

StartUid length < 8 for key: %q, parsed key: %+v

Error message

StartUid length < 8 for key: %q, parsed key: %+v

What it means

Error returned by x/keys.go while parsing a key when the remaining bytes contain fewer than 8 bytes for the StartUid field. The raw key and parsed structure are reported via %q and %+v. Indicates a truncated or malformed key; fix by correcting or regenerating the key data.

Source

Thrown at x/keys.go:592

		}
		if !p.HasStartUid {
			break
		}

		if len(k) != 16 {
			return p, errors.Errorf("StartUid length != 8 for key: %q, parsed key: %+v", key, p)
		}

		k = k[8:]
		p.StartUid = binary.BigEndian.Uint64(k)
	case ByteIndex:
		if !p.HasStartUid {
			p.Term = string(k)
			break
		}

		if len(k) < 8 {
			return p, errors.Errorf("StartUid length < 8 for key: %q, parsed key: %+v", key, p)
		}

		term := k[:len(k)-8]
		startUid := k[len(k)-8:]
		p.Term = string(term)
		p.StartUid = binary.BigEndian.Uint64(startUid)
	case ByteCount, ByteCountRev:
		if len(k) < 4 {
			return p, errors.Errorf("count length < 4 for key: %q, parsed key: %+v", key, p)
		}
		p.Count = binary.BigEndian.Uint32(k)

		if !p.HasStartUid {
			break
		}

		if len(k) != 12 {
			return p, errors.Errorf("StartUid length != 8 for key: %q, parsed key: %+v", key, p)

View on GitHub (pinned to 759e242be6)

Solutions

1. Inspect the key bytes and ensure there are at least 8 trailing bytes for the StartUid
2. Regenerate the index key via the library's index-key helpers
3. Check the writer that produced the key for truncation bugs
4. If persistent in storage, treat as corruption and restore

Example fix

// before: index key missing start uid bytes
key := []byte{byte(x.ByteIndex)} // only 1 byte payload
p, err := x.Parse(key) // StartUid length < 8
// after
key := x.IndexKey(attr, term, startUid) // term + 8-byte startUid

if len(key) < 9 { return fmt.Errorf("index key too short: %d", len(key)) }
ok, err := x.IsDropOpKey(key)

func isMinIndexKey(key []byte) bool { return len(key) >= 9 }

When it happens

Trigger: Calling Parse/IsDropOpKey with a ByteIndex key where HasStartUid is true but len(k) < 8, i.e. the term portion is empty or the StartUid bytes are missing.

Common situations: Corrupted index keys on disk, keys truncated by manual slicing, or test fixtures with empty terms where a start-uid key was expected.

Related errors

• Invalid UID with value 0 for key: %v
• StartUid length != 8 for key: %q, parsed key: %+v
• count length < 4 for key: %q, parsed key: %+v
• Invalid data type
• could not parse key %s

AI-assisted analysis of dgraph-io/dgraph@759e242be6 (2026-09-01). Data as JSON: /api/errors/12d28a1fe1dc7ebd. Report an issue: GitHub.