jackc/pgx · error

cannot scan NULL into *uint16

Error message

cannot scan NULL into *uint16

What it means

uint16Wrapper.ScanInt64 received an invalid (NULL) Int8 while the destination is a plain Go uint16, which cannot represent NULL.

Solutions

1. Scan into *uint16 or a nullable type
2. Filter NULLs in the query

When it happens

Trigger: Thrown at pgtype/builtin_wrappers.go:159 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/8ea1b2982d5d4534. Report an issue: GitHub.

Appendix: source

Thrown at pgtype/builtin_wrappers.go:159

	if v.Int64 > math.MaxUint8 {
		return fmt.Errorf("%d is greater than maximum value for uint8", v.Int64)
	}
	*w = uint8Wrapper(v.Int64)

	return nil
}

func (w uint8Wrapper) Int64Value() (Int8, error) {
	return Int8{Int64: int64(w), Valid: true}, nil
}

type uint16Wrapper uint16

func (w uint16Wrapper) SkipUnderlyingTypePlan() {}

func (w *uint16Wrapper) ScanInt64(v Int8) error {
	if !v.Valid {
		return fmt.Errorf("cannot scan NULL into *uint16")
	}

	if v.Int64 < 0 {
		return fmt.Errorf("%d is less than minimum value for uint16", v.Int64)
	}
	if v.Int64 > math.MaxUint16 {
		return fmt.Errorf("%d is greater than maximum value for uint16", v.Int64)
	}
	*w = uint16Wrapper(v.Int64)

	return nil
}

func (w uint16Wrapper) Int64Value() (Int8, error) {
	return Int8{Int64: int64(w), Valid: true}, nil
}

type uint32Wrapper uint32

View on GitHub (pinned to ec1a0befd2)