我正在将我从自定义CMS管理的网站移动到Wordpress，并且发现图像标记上的某些属性在WP环境中显示有问题。要解决此问题，我需要删除内联到post_content表的wp_posts列中每个图像标记的height属性。
从数据库中的原始值开始，我需要以下内容：
<img src="http://example.com/img/20150823_image.jpg" style="width: 730px; height: 730px;" />
成为：
<img src="http://example.com/img/20150823_image.jpg" style="width: 730px;" />
所以，基本上，我需要删除＆＃34;身高：730px;＆＃34;一部分。它是图像特定的，所以在这种情况下它是730但在另一个它可能是1500,447,80等。
我试图看看我是否可以使用＆＃39;％＆＃39;作为一个通配符，但似乎没有工作......
UPDATE wp_posts SET post_content = REPLACE(post_content,' height: %px;','');
任何帮助都会非常感激，因为我不需要手动浏览数千行来删除它们。
答案 0 :(得分：2)
您可以使用函数进行文本解析：
create function f_strip_height( in_s text ) returns text
begin
declare v_start int;
declare v_end int;
declare v_height text;
select locate(' height:', in_s ) into v_start;
if (v_start>0) then
select locate( 'px;', substring( in_s, v_start) ) into v_end;
select trim(substring(substring( in_s, v_start, v_end+2), 9)) into v_height;
if (v_end>0 and concat(cast(v_height as unsigned), 'px;' = v_height)) then
return concat(substring( in_s, 1, v_start-1), substring( in_s, v_start+v_end+2));
end if;
end if;
return in_s;
end
然后使用函数：
UPDATE wp_posts SET post_content = f_strip_height(post_content);
答案 1 :(得分：1)
这不是SQL的工作。这是一个简单的（？）PHP脚本应该可以解决这个问题，尽管我这样做是不可能的，所以不能保证：
<?php
// create the DB connection
$db = new PDO("mysql:host=localhost;dbname=wordpress", "user", "password");
// quiet warnings
libxml_use_internal_errors(true);
// prepare the update statement for later
$stmt = $db->prepare("UPDATE wp_posts SET post_content = ? WHERE post_id = ?");
// select the posts that at least have the word "height:" in them
$posts = $db->query("SELECT post_id, post_content FROM wp_posts WHERE post_content LIKE '%height:%'");
// loop through the posts
while ($post = $posts->fetch(PDO::FETCH_ASSOC)) {
// create a DOM document
$dom = new DomDocument();
// load the HTML into the DOM parser
$dom->loadHTML($post["post_content"], LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD);
// prepare the XPath
$xpath = new DomXPath($dom);
// get all img elements with a style attribute containing the word height
$imgs = $xpath->query("//img[contains(@style, 'height')]");
foreach ($imgs as $img) {
// get the style attribute value
$style = $img->getAttribute("style");
// remove height
$style = preg_replace("/height\s*:\s*\d+(px)?;?/", "", $style);
// replace the attribute value
$img->setAttribute("style", $style);
}
// output the new HTML
$newhtml = $dom->saveHTML();
echo "Updating post $post["post_id"] with new content:\n$newhtml\n\n";
// save it into the database -- uncomment this line when you trust the script!
// $stmt->execute([$newhtml, $post["post_id"]]);
}
答案 2 :(得分：1)
如果您拥有相应的权限，则可以使用UDF 27.4.2 Adding a New User-Defined Function，其中一些可以是：
在另一种情况下，如前所述，您可以执行自己的功能，这里有一个可以根据需要修改和调整的版本：
mysql> DROP TABLE IF EXISTS `wp_posts`;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE IF NOT EXISTS `wp_posts` (
-> `post_content` TEXT
-> );
Query OK, 0 rows affected (0.00 sec)
mysql> INSERT INTO `wp_posts`
-> (`post_content`)
-> VALUES
-> ('<img src="http://example.com/img/20150823_image.jpg" style="width: 730px; height: 730px;" />'),
-> ('<img src="http://example.com/img/20150824_image.jpg" style="width: 730px; height: 1500px;" />'),
-> ('<img src="http://example.com/img/20150825_image.jpg" style="width: 730px; height: 80px;" />'),
-> ('<img src="http://example.com/img/20150826_image.jpg" style="width: 730px; height: 0px;" />'),
-> ('<img src="http://example.com/img/20150827_image.jpg" style="width: 730px;" />');
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> DELIMITER //
mysql> DROP FUNCTION IF EXISTS `get_string`//
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE FUNCTION `get_string`(`_string` TEXT,
-> `_begin` VARCHAR(255),
-> `_end` VARCHAR(255))
-> RETURNS TEXT DETERMINISTIC
-> BEGIN
-> DECLARE `_begin_pos` INT UNSIGNED DEFAULT LOCATE(`_begin`, `_string`);
-> DECLARE `_end_pos` INT UNSIGNED DEFAULT 0;
-> IF `_begin_pos` IS NOT NULL AND `_begin_pos` > 0 THEN
-> SET `_end_pos` := LOCATE(`_end`, `_string`, `_begin_pos`);
-> IF `_end_pos` IS NOT NULL AND `_end_pos` > 0 THEN
-> RETURN SUBSTRING(`_string`,
-> `_begin_pos`,
-> (`_end_pos` + CHAR_LENGTH(`_end`)) - `_begin_pos`);
-> END IF;
-> END IF;
-> RETURN '';
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql> SELECT `post_content`
-> FROM `wp_posts`;
+-----------------------------------------------------------------------------------------------+
| post_content |
+-----------------------------------------------------------------------------------------------+
| <img src="http://example.com/img/20150823_image.jpg" style="width: 730px; height: 730px;" /> |
| <img src="http://example.com/img/20150824_image.jpg" style="width: 730px; height: 1500px;" /> |
| <img src="http://example.com/img/20150825_image.jpg" style="width: 730px; height: 80px;" /> |
| <img src="http://example.com/img/20150826_image.jpg" style="width: 730px; height: 0px;" /> |
| <img src="http://example.com/img/20150827_image.jpg" style="width: 730px;" /> |
+-----------------------------------------------------------------------------------------------+
5 rows in set (0.00 sec)
mysql> UPDATE `wp_posts`
-> SET `post_content` = REPLACE(`post_content`, `get_string`(`post_content`, ' height:', ';'), '');
Query OK, 4 rows affected (0.01 sec)
Rows matched: 5 Changed: 4 Warnings: 0
mysql> SELECT `post_content`
-> FROM `wp_posts`;
+-------------------------------------------------------------------------------+
| post_content |
+-------------------------------------------------------------------------------+
| <img src="http://example.com/img/20150823_image.jpg" style="width: 730px;" /> |
| <img src="http://example.com/img/20150824_image.jpg" style="width: 730px;" /> |
| <img src="http://example.com/img/20150825_image.jpg" style="width: 730px;" /> |
| <img src="http://example.com/img/20150826_image.jpg" style="width: 730px;" /> |
| <img src="http://example.com/img/20150827_image.jpg" style="width: 730px;" /> |
+-------------------------------------------------------------------------------+
5 rows in set (0.00 sec)
Rextester中的示例。