类 yii\db\ColumnSchemaBuilder

                public function __construct($type, $length = null, $db = null, $config = [])
{
    $this->type = $type;
    $this->length = $length;
    $this->db = $db;
    parent::__construct($config);
}

            

                public function __toString()
{
    switch ($this->getTypeCategory()) {
        case self::CATEGORY_PK:
            $format = '{type}{check}{comment}{append}';
            break;
        default:
            $format = '{type}{length}{notnull}{unique}{default}{check}{comment}{append}';
    }
    return $this->buildCompleteString($format);
}

            

                public function after($after)
{
    $this->after = $after;
    return $this;
}

            

                public function append($sql)
{
    $this->append = $sql;
    return $this;
}

            

                protected function buildAfterString()
{
    return '';
}

            

                protected function buildAppendString()
{
    return $this->append !== null ? ' ' . $this->append : '';
}

            

                protected function buildCheckString()
{
    return $this->check !== null ? " CHECK ({$this->check})" : '';
}

            

                protected function buildCommentString()
{
    return '';
}

            

                protected function buildCompleteString($format)
{
    $placeholderValues = [
        '{type}' => $this->type,
        '{length}' => $this->buildLengthString(),
        '{unsigned}' => $this->buildUnsignedString(),
        '{notnull}' => $this->buildNotNullString(),
        '{unique}' => $this->buildUniqueString(),
        '{default}' => $this->buildDefaultString(),
        '{check}' => $this->buildCheckString(),
        '{comment}' => $this->buildCommentString(),
        '{pos}' => $this->isFirst ? $this->buildFirstString() : $this->buildAfterString(),
        '{append}' => $this->buildAppendString(),
    ];
    return strtr($format, $placeholderValues);
}

            

                protected function buildDefaultString()
{
    $defaultValue = $this->buildDefaultValue();
    if ($defaultValue === null) {
        return '';
    }
    return ' DEFAULT ' . $defaultValue;
}

            

                protected function buildDefaultValue()
{
    if ($this->default === null) {
        return $this->isNotNull === false ? 'NULL' : null;
    }
    switch (gettype($this->default)) {
        case 'double':
            // ensure type cast always has . as decimal separator in all locales
            $defaultValue = StringHelper::floatToString($this->default);
            break;
        case 'boolean':
            $defaultValue = $this->default ? 'TRUE' : 'FALSE';
            break;
        case 'integer':
        case 'object':
            $defaultValue = (string) $this->default;
            break;
        default:
            $defaultValue = "'{$this->default}'";
    }
    return $defaultValue;
}

            

                protected function buildFirstString()
{
    return '';
}

            

                protected function buildLengthString()
{
    if ($this->length === null || $this->length === []) {
        return '';
    }
    if (is_array($this->length)) {
        $this->length = implode(',', $this->length);
    }
    return "({$this->length})";
}

            

                protected function buildNotNullString()
{
    if ($this->isNotNull === true) {
        return ' NOT NULL';
    } elseif ($this->isNotNull === false) {
        return ' NULL';
    }
    return '';
}

            

                protected function buildUniqueString()
{
    return $this->isUnique ? ' UNIQUE' : '';
}

            

                protected function buildUnsignedString()
{
    return '';
}

            

                public function check($check)
{
    $this->check = $check;
    return $this;
}

            

                public function comment($comment)
{
    $this->comment = $comment;
    return $this;
}

            

                public function defaultExpression($default)
{
    $this->default = new Expression($default);
    return $this;
}

            

                public function defaultValue($default)
{
    if ($default === null) {
        $this->null();
    }
    $this->default = $default;
    return $this;
}

            

                public function first()
{
    $this->isFirst = true;
    return $this;
}

            

                public function getCategoryMap()
{
    return static::$typeCategoryMap;
}

            

                protected function getTypeCategory()
{
    return isset($this->categoryMap[$this->type]) ? $this->categoryMap[$this->type] : null;
}

            

                public function notNull()
{
    $this->isNotNull = true;
    return $this;
}

            

                public function null()
{
    $this->isNotNull = false;
    return $this;
}

            

                public function setCategoryMap($categoryMap)
{
    static::$typeCategoryMap = $categoryMap;
}

            

                public function unique()
{
    $this->isUnique = true;
    return $this;
}

            

                public function unsigned()
{
    switch ($this->type) {
        case Schema::TYPE_PK:
            $this->type = Schema::TYPE_UPK;
            break;
        case Schema::TYPE_BIGPK:
            $this->type = Schema::TYPE_UBIGPK;
            break;
    }
    $this->isUnsigned = true;
    return $this;
}