vitessio/vitess · error

unexpected type %T: %v

Error message

unexpected type %T: %v

What it means

InterfaceToValue converts a limited set of Go types (int64, uint64, float64, string and similar numeric cases above) into a sqltypes.Value. Any other Go dynamic type hits the default branch and returns this error naming the type and value.

Source

Thrown at go/sqltypes/value.go:315

// string and []byte.
// This function is deprecated. Use the type-specific
// functions instead.
func InterfaceToValue(goval any) (Value, error) {
	switch goval := goval.(type) {
	case nil:
		return NULL, nil
	case []byte:
		return MakeTrusted(VarBinary, goval), nil
	case int64:
		return NewInt64(goval), nil
	case uint64:
		return NewUint64(goval), nil
	case float64:
		return NewFloat64(goval), nil
	case string:
		return NewVarChar(goval), nil
	default:
		return NULL, fmt.Errorf("unexpected type %T: %v", goval, goval)
	}
}

// Type returns the type of Value.
func (v Value) Type() querypb.Type {
	return querypb.Type(v.typ)
}

// Raw returns the internal representation of the value. For newer types,
// this may not match MySQL's representation.
func (v Value) Raw() []byte {
	return v.val
}

// RawStr returns the internal representation of the value as a string instead
// of a byte slice. This is equivalent to calling `string(v.Raw())` but does
// not allocate.
func (v Value) RawStr() string {

View on GitHub (pinned to 01a25a7d17)

Solutions

1. Normalize the input to one of the supported types (int64/uint64/float64/string) before calling
2. Convert bools to 0/1 ints, []byte to string, time.Time to formatted string
3. For JSON values, marshal the nested value to a string and use a JSON-typed Value

Example fix

// before
v, err := sqltypes.InterfaceToValue(true)
// after
var i int64
if b { i = 1 }
v, err := sqltypes.InterfaceToValue(i)

func supportedGoType(v any) bool {
  switch v.(type) {
  case int64, uint64, float64, string:
    return true
  }
  return false
}

func isScalar(v any) bool {
  switch v.(type) {
  case int64, uint64, float64, string:
    return true
  default:
    return false
  }
}

v, err := sqltypes.InterfaceToValue(x)
if err != nil {
  return sqltypes.NewVarBinary(fmt.Sprintf("%v", x)) // fallback
}

When it happens

Trigger: Calling InterfaceToValue with e.g. bool, []byte, time.Time, nil, or a struct — typically via Value.UnmarshalJSON when a JSON bind variable contains a JSON object/array/bool rather than number or string.

Common situations: Unmarshaling JSON bind variables where users pass booleans, nested objects, or null; passing Go-native values from application code straight into vitess bind var conversion without normalizing.

Related errors

• unreachable
• Invalid JSON path expression.
• range %d should be >= %d
• too big depth for the nested JSON; it exceeds %d
• unexpected character %q in JSON

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/e9a7249850f1d1d4. Report an issue: GitHub.