vitessio/vitess · error

UnescapeID err: unexpected single backtick at position %d in

Error message

UnescapeID err: unexpected single backtick at position %d in '%s'

What it means

Returned by sqlescape.UnescapeID when a backtick-quoted identifier contains an unexpected single backtick at the given position, i.e. a stray or unpaired backtick inside the identifier.

Source

Thrown at go/sqlescape/ids.go:75

// UnescapeID reverses any backticking in the input string by EscapeID.
func UnescapeID(in string) (string, error) {
	l := len(in)

	if l == 0 || in == "``" {
		return "", fmt.Errorf("UnescapeID err: invalid input identifier '%s'", in)
	}

	if l == 1 {
		if in[0] == '`' {
			return "", errors.New("UnescapeID err: invalid input identifier '`'")
		}
		return in, nil
	}

	first, last := in[0], in[l-1]

	if first == '`' && last != '`' {
		return "", fmt.Errorf("UnescapeID err: unexpected single backtick at position %d in '%s'", 0, in)
	}
	if first != '`' && last == '`' {
		return "", fmt.Errorf("UnescapeID err: unexpected single backtick at position %d in '%s'", l, in)
	}
	if first != '`' && last != '`' {
		if idx := strings.IndexByte(in, '`'); idx != -1 {
			return "", fmt.Errorf("UnescapeID err: no outer backticks found in the identifier '%s'", in)
		}
		return in, nil
	}

	in = in[1 : l-1]

	if found := strings.Contains(in, "`"); !found {
		return in, nil
	}

	var buf strings.Builder

View on GitHub (pinned to 01a25a7d17)

Solutions

1. Ensure identifiers are escaped/paired with EscapeID rather than hand-built strings
2. Validate balanced backticks before calling UnescapeID
3. Trace where the string was truncated and fix the producer

Example fix

// before
name, err := sqlescape.UnescapeID(raw)
// after
if strings.Count(raw, "`")%2 != 0 {
	return fmt.Errorf("unbalanced backticks in %q", raw)
}
name, err := sqlescape.UnescapeID(raw)

func balancedBackticks(in string) bool { return strings.Count(in, "`")%2 == 0 }

func isQuotedID(in string) bool { return len(in) >= 2 && in[0] == '`' && in[len(in)-1] == '`' }

if !isQuotedID(raw) && strings.Contains(raw, "`") {
	return fmt.Errorf("malformed identifier %q", raw)
}
name, err := sqlescape.UnescapeID(raw)

When it happens

Trigger: Calling UnescapeID on a string like "`tablename" — opening backtick present, closing one missing.

Common situations: String truncation (e.g. log parsing, config splitting on backticks), hand-built identifiers where only one side was quoted, copy-paste errors.

Related errors

• UnescapeID err: no outer backticks found in the identifier '
• UnescapeID err: invalid input identifier '%s'
• unknown SQL type %q at %s
• --batch-size only allowed when all queries are CREATE TABLE|
• missing value for 'rate'

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/e0176e5d05286ba3. Report an issue: GitHub.