我正在将大约500篇帖子（实际上是WooCommerce产品）迁移到一个新的自定义帖子类型（使用Convert Post Types插件），并希望同时迁移类别。

有一个Taxonomy Converter插件，它可以迁移类别本身，但不能迁移它们的层次结构，尽管它说会迁移。

还有简单的跑步：

UPDATE wp_term_taxonomy SET taxonomy=\'project-category\' WHERE taxonomy=\'product_cat\';

我可以手动调整层次结构，这是我目前倾向的，但我遇到了some code 这是几年前的作品，我对它进行了一些更新，希望能看到一些作品。它包括在下面。

递归迭代器返回的每一行如下所示：

Array
(
    [term_id] => 39
    [description] => Bla bla bla
    [parent] => 0
    [count] => 7
    [name] => Security Bars
    [slug] => security-bars
)

但我不清楚这些信息要插入哪里。我认为大致如下：

$qry = $wpdb->insert(\'wp_term_taxonomy\', array(
                            \'term_id\' => $row[\'term_id\'],
                            \'taxonomy\' => \'project-category\',
                            \'description\' => $row[\'description\'],
                            \'parent\' => $parent_id
                        )); 

但这仍然没有给我等级制度。我想这是因为parent 需要是身份证wp_term_taxonomy 我刚刚创建了。

有什么建议吗？一个可以做到这一点的插件将受到欢迎。

迄今为止的代码：

class RecursiveCategoryIterator implements RecursiveIterator {
    const ID_FIELD = \'term_id\';
    const PARENT_FIELD = \'parent\';

    private $_data;
    private $_root;
    private $_position = 0;

    public function __construct(array $data, $root_id = 0) {
        $this->_data = $data;
        $this->_root = $root_id;
    }

    public function valid() {
        return isset($this->_data[$this->_root][$this->_position]);
    }

    public function hasChildren() {
        $subid = $this->_data[$this->_root][$this->_position][self::ID_FIELD];
        return isset($this->_data[$subid])
            && is_array($this->_data[$subid]);
    }

    public function next() {
        $this->_position++;
    }

    public function current() {
        return $this->_data[$this->_root][$this->_position];
    }

    public function getChildren() {
        return new self($this->_data,
            $this->_data[$this->_root][$this->_position][self::ID_FIELD]);
    }

    public function rewind() {
        $this->_position = 0;
    }

    public function key() {
        return $this->_position;
    }

    public static function createFromResult($result) {
        $menu_array = array();
        foreach($result as $row) {
            $menu_array[$row[self::PARENT_FIELD]][] = $row;
        }

        return new self($menu_array);
    }
}

使用它的功能：

function migrate_terms() {

    $sql="SELECT a.term_id,a.description,a.parent,a.count,b.name,b.slug
    FROM wp_term_taxonomy a INNER JOIN wp_terms b WHERE a.term_id=b.term_id
    AND a.taxonomy=\'product_cat\';
    ";
    global $wpdb;
    $result = $wpdb->get_results($sql, ARRAY_A);

    // always test for failure
    if($result === false) {
        die("query failed: ". $wpdb->show_errors() );
    }

    // create the iterator from the result set
    $wpterms = RecursiveCategoryIterator::createFromResult($result);
        // Look at it
        echo "<pre>";
        print_r($wpterms);
        echo "</pre>";
    // and import it. 
    //insert_it($wpterms, 0);

}

以及“完成所有脏活的功能”：

function insert_it($iterator, $parent_id = 0) {
    foreach($iterator as $row) {
        // insert the row, just edit the query, and don\'t forget
        // to escape the values. if you have an insert function,
        // use it by all means
        $qry = $wpdb->insert(WHAT GOES HERE?);

        $status = $wpdb->get_results($qry);

        if($status === false) {
            // insert failed - rollback and abort
            die("hard: " . $wpdb->show_errors() );
        }

        // you need to pass the id of the new row
        // so the "child rows" have their respective parent
        $cid = $wpdb->insert_id;

        // insert the children too
        if($iterator->hasChildren()) {
            insert_it($iterator->getChildren(), $cid);
        }
    }
}    

// Now we set that function up to execute when the admin_notices action is called
add_action( \'admin_notices\', \'migrate_terms\' );