56
votes
Accepted
Explanation of update_post_(meta/term)_cache
Object cache everywhere
WordPress tries to reduce the number of database queries as much as possible.
For example, anytime you get a meta field or a taxonomy field, before querying the database, ...
- 45.9k
29
votes
Accepted
Getting failure when using filemtime() with wp_enqueue_style
It's because you're retrieving it via URL, but filemtime() requires a path. Use get_stylesheet_directory() instead. That returns a path:
function pro_styles()
{
wp_enqueue_style( 'child-style', ...
- 42.5k
22
votes
Any reason why wp_cache_set not to work?
As of WordPress 6.3, both WP_Query and WP_User_Query automatically cache requests. The original question example is outdated since get_posts() uses WP_Query.
The wp_cache_*() functions are non-...
- 20.5k
19
votes
Accepted
Should I use Transient API to store HTML String, or Object?
Should I use Transient API at all here?
No.
In a stock WordPress install transients are stored in the wp_options table, and only cleaned up during core upgrades. Suppose you have 50,000 posts, that'...
- 2,573
19
votes
Accepted
Is get_option() faster than accessing get_transient()?
Today I run a test over my db to explore the speed difference between accessing a key from options, custom table & transients. I ran the test for 1000 times and following is the time taken to run ...
- 58.2k
12
votes
Should I use Transient API to store HTML String, or Object?
Not All WP Code Is Public Code
If you are going to release something public, then all the things kovshenin said are perfectly valid.
Things are different if you are going to write private code for ...
- 45.9k
12
votes
Accepted
How to cache bust a child theme style.css
@dalbaeb's comment eventually lead to insightful discussions and a feasible solution. Thanks a lot!
I believe the reason my child theme CSS was loaded using 'ver=<parent-theme-version> was ...
- 361
12
votes
Accepted
Is it possible to completely stop WP_Query retrieving posts?
At the moment, it is not possible.
When 'pre_get_posts' runs, is too late to stop WP_Query to perform a query.
WordPress itself, when you try to query a taxonomy that does not exists, adds AND (0 = ...
- 45.9k
11
votes
Accepted
How can I clear oEmbed caches for YouTube on posts as they are loaded
How to trigger an oembed cache regeneration
The default cache time is 24 hours and we can adjust it with the oembed_ttl filter.
But as you've noticed, expired cache is not enough to trigger a cache ...
- 66.7k
10
votes
Accepted
Using get_posts vs. WP_Query
Edit: WP Core has changed since the question and answer were written. While I still believe it's better to use WP_Query for other reasons, the suppress_filters rule should be gone from WPCS/VIPCS now
...
- 58.2k
9
votes
Forcing reload of editor-style.css
I couldn't get toscho's answer to work for the current version of WordPress (4.7.2), and that seems to be because the TinyMCE init array has a cache_suffix set to 'wp-mce-' . $tinymce_version.
So ...
- 93
8
votes
Accepted
Is define('WP_CACHE', true) needed for object caching?
No, including this constant with a value of true loads advanced-cache.php. Object-cache.php is loaded and used automatically.
See https://wordpress.org/support/article/editing-wp-config-php/
- 985
7
votes
Accepted
wp_cache_set() or wp_cache_add()
According with WP Object API documentation both functions accepts these arguments:
$key: the key to indicate the value.
$data: the value you want to store.
$group: (optional) this is a way of ...
- 20.3k
6
votes
How can I cache WordPress Rest API Response
You should create a new instance from WP_REST_Response to set the Cache-Control value.
<?php
register_rest_route('wp/v2', '/your_endpoint', array(
'methods' => 'GET',
'callback' => '...
- 765
5
votes
Accepted
Nginx FastCGI_Cache Vs PHP Caching
Nginx is really good at concurrency (PHP not so much) so you should try a bit more than 180 requests per second. Maybe 500, or 1000 depending on your server resources and network throughput.
The ...
- 2,573
5
votes
Getting "Fatal error: Call to undefined function wp_cache_get() in option.php" after updating a cache plugin
I solved deleting the w3tc cache plugin from ftp
5
votes
Accepted
Is there a get_post(s) filter that can alter/replace the output completely?
If you look towards the end of the query process (which starts with the pre_get_posts filter), there is a filter called the_posts (not to be confused with the_post). This allows you to modify the ...
- 14.1k
5
votes
Getting failure when using filemtime() with wp_enqueue_style
Just to expand on Jacob Peattie Answer for people that have CSS file in a custom plugin, you can use
filemtime( plugin_dir_path(dirname(__FILE__)).'plugin-folder/css-file-path.css' )
5
votes
Wordpress transients for a shortcode
I add it the transient name to a variable to handle it easier.
Next, I check if the return value from the get_transient is false and update the variable name and the transient.
You can try this one:
...
- 1,606
5
votes
Is get_option() faster than accessing get_transient()?
If no object caching is found, get_transient calls get_option twice, once or the expiry interval and one for the value, therefor it is not going to be faster.
get_option performance by itself will be ...
- 23.2k
5
votes
Accepted
How can I free up the memory used by update_post_meta?
It turns out that it was due to Query Monitor, a plugin that records info about each query. Every time update_post_meta ran, Query Monitor would store some data about the query, which eventually added ...
- 598
4
votes
Explanation of update_post_(meta/term)_cache
The main point of interest here is the update_post_caches function. It is called after WP_Query got all the posts from the DB. Usually, the reason you want the posts in the first place is to display ...
- 23.2k
4
votes
Usage of Direct Database Call Without Caching Error
I agree with @Tom J Nowell:
I'd suggest you remove it, or better yet just say "all rights reserved".
But in the quest for answers, here's a suggestion using an option field to cache the years:
/*...
- 36.3k
4
votes
wp_transients | wp_object_cache VS SESSIONS & Cookies?
set_transient() using wp_cache_set() and mysql database. WP Cache API using $GLOBAL(global session for application).
Cookies and Session saves data only for one current user(cookies in browser, ...
- 76
4
votes
Accepted
Should i clear the plugin cache for cache busting?
The main obvious problem with your scheme is that when someone wil try to reload an old page it will get all kinds of 404 when requesting the JS and CSS since those files are not on the server anymore....
- 23.2k
4
votes
Automatically Refresh WordPress Stylesheet
"Quick" fix: Right Click -> view page source ( ctrl+U ), find .css file you changed, open it in new tab and reload ( you should see change in place you've made it )
ONLY in development mode add php ...
- 41
4
votes
Want to enforce the visitor to load the new version of your stylesheets and scripts
Sounds like you are talking about cachebusting. Changing the querystring makes the browser interpret the URL as a new resource. Unless you want to change the entire filename there really isn't a ...
- 5,071
4
votes
Why my browser keeps loading old version of custom JavaScript files in \divi\js?
First get datetime stamp of your js file's last modification, and use it as fourth parameter of wp_enqueue_script function:
$path = 'full path to your script file');
$handle = 'your_handle';
$src = '...
- 3,344
4
votes
Accepted
Wordpress transients for a shortcode
Use this instead of the line in wich you define $days (your second line):
$transient = get_transient( 'your_transient_key' );
if( !$transient ):
$days = file_get_contents( 'json_file' );
...
- 428
Only top scored, non community-wiki answers of a minimum length are eligible