src/Builder/Syntax/PlaceholderWriter.php
protected function setValidSqlValue($value)
    {
        $value = $this->writeNullSqlString($value);
        $value = $this->writeStringAsSqlString($value);
        $value = $this->writeBooleanSqlString($value);

        return $value;
    }
protected function setValidSqlValue($value)
    {
        $value = $this->writeNullSqlString($value);
        $value = $this->writeStringAsSqlString($value);
        $value = $this->writeBooleanSqlString($value);

        return $value;
    }
@param $value

@return string