I would like to run this type of query on my WP database to remove all span instances with id="more-":
UPDATE wp_posts SET post_content = REPLACE (
post_content,
'<p><span id="more-35075"></span></p>',
'');
But the number that follows the 'more-' in my example is a variable. How to write this query with someting like a wildcard: span id="more-*.
Thank you
In MySQL version 8.0 and above, you can use REGEX_REPLACE() function. In absence of the same, some complicated string operations can be done. This is based on your confirmation, that the said sub-string is occurring only once in a value.
REPLACE() does not have any support for wildcards, patterns, regular expressions etc. It only replaces a given fixed substring with another fixed substring, in a bigger string.
Instead, we can try to extract portions of the post_content. We will extract the leading substring before the '<p><span id="more-' using Substring_Index() function. Similarly, we will extract the trailing substring after the '"></span></p>' portion.
Now, we can simply Concat() these portions to get the required post_content. You can find details of various String functions used here: https://dev.mysql.com/doc/refman/8.0/en/string-functions.html
I have also added a WHERE condition, so that we pick only those rows which match our given substring criteria.
UPDATE wp_posts
SET post_content =
CONCAT(
SUBSTRING_INDEX(post_content,
'<p><span id="more-',
1),
SUBSTRING(post_content,
LOCATE('"></span></p>',
post_content,
LOCATE('<p><span id="more-',
post_content)
) + 13) -- 13 is character length of "></span></p>
)
WHERE post_content LIKE '%<p><span id="more-%"></span></p>%';
Query #1: Data before Update operations
SELECT * FROM wp_posts;
| post_content |
| ------------------------------------------------------- |
| adasdaadsa<p><span id="more-35075"></span></p>121324124 |
| 1412123123<p><span id="more-232"></span></p>adasdaafas |
Query #2: Data after Update operations
SELECT * FROM wp_posts;
| post_content |
| -------------------- |
| adasdaadsa121324124 |
| 1412123123adasdaafas |
wp_posts); most likely OP has no control over it.