jackc/pgx · error

jsonb too short

Error message

jsonb too short

What it means

The binary JSONB wire format prefixes every value with a one-byte version header. This guard fires when a non-NULL jsonb payload in binary format contains zero bytes, so there is no version byte to inspect — the source buffer is truncated below the minimum 1-byte length the format requires.

Solutions

1. Treat this as data corruption: verify the column really holds jsonb and the binary format was requested correctly
2. Use text format for the column instead of binary if the server/driver combination produces empty payloads
3. Check for a truncated or misallocated buffer if the value was produced by custom encoding logic

When it happens

Trigger: Thrown at pgtype/jsonb.go:68 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of jackc/pgx@ec1a0befd2 (2026-08-04). Data as JSON: /api/errors/79fc0a6966f4e08e. Report an issue: GitHub.

Appendix: source

Thrown at pgtype/jsonb.go:68

		}
	case TextFormatCode:
		return (&JSONCodec{Marshal: c.Marshal, Unmarshal: c.Unmarshal}).PlanScan(m, oid, format, target)
	}

	return nil
}

type scanPlanJSONBCodecBinaryUnwrapper struct {
	textPlan ScanPlan
}

func (plan *scanPlanJSONBCodecBinaryUnwrapper) Scan(src []byte, dst any) error {
	if src == nil {
		return plan.textPlan.Scan(src, dst)
	}

	if len(src) == 0 {
		return fmt.Errorf("jsonb too short")
	}

	if src[0] != 1 {
		return fmt.Errorf("unknown jsonb version number %d", src[0])
	}

	return plan.textPlan.Scan(src[1:], dst)
}

func (c *JSONBCodec) DecodeDatabaseSQLValue(m *Map, oid uint32, format int16, src []byte) (driver.Value, error) {
	if src == nil {
		return nil, nil
	}

	switch format {
	case BinaryFormatCode:
		if len(src) == 0 {
			return nil, fmt.Errorf("jsonb too short")

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