Updating User Meta with SQL Query

How can I write a bulk MySQL command to add in the value wp_capabilites=”a:1:{s:10:”subscriber”;b:1;}” into each user_id except 1, 2 and 3 ie. the newly imported users? You don’t. That is a serialized array which is a PHP construct. MySQL has no idea what to do with it. To the database, it is just an … Read more

wpdb Custom Meta Data with 2 conditions

I found my error in the above query. There still may be a better way to do this, thank you kaiser, and I will update once I’ve done more study. What I forgot to do was GROUP_CONCAT another meta_value so i could pull out different bits. It still seems longer than it needs to be, … Read more

#1115 – Unknown character set: ‘utf8mb4’

WordPress does not support MySQL 4 : To run WordPress your host just needs a couple of things: MySQL version 5.0 or greater (recommended: MySQL 5.5 or greater) https://wordpress.org/about/requirements/ While the utf8mb4 encoding is recent change and you might work around it, overall you still need compatible MySQL version.

Fulltext search in posts sorted by relevancy

You may want to check the Sphinx search engine http://sphinxsearch.com/ It took me about one day to set it up and learn how to use, but it does really good job with sorting by relevancy and grammar stemming. Also it is faster than fulltext search for big data sets thanks to indexing.

SQL query to update post_date (one post = one single date & time)

I would not do this with SQL. A relatively simple PHP loop should work. function bulk_schedule_posts_wpse_105834() { $args = ( array( ‘cat’ => 1, ‘posts_per_page’ => -1, ‘post_status’ => ‘draft’, ‘post_type’ => ‘post’, ) ); $posts = new WP_Query($args); if (!$posts->have_posts()) return false; $date=”2013-08-01″; $times = array( ’10:00′, ’14:00′, ’17:00′, ’20:30′ ); while ($posts->have_posts()) { … Read more

Using source control with WordPress

Have a look at this older question: How to: Easily Move a WordPress Install from Development to Production?. It covers migration and deployment of WP installations. For your more immediate issue, do backups of your database. Use a backup plugin (WP-DB-Backup is what I use, find it on the WP plugins repository) to handle this … Read more

Increment value (value = value+1) of $wpdb->update

You don’t. Not with the WPDB update() function. The update function assumes that the values of the columns are strings. You can override that with the format parameter, but that only allows %d, %f, and %s (integer, float, string). It doesn’t allow operations on columns like total+1. You’d have to use the query() function directly … Read more

Programmatically changing role information; editing role name and deleting

There’s a whole host of functions specifically for this purpose; http://codex.wordpress.org/Function_Reference#User_and_Author_Functions Of particular interest (but not limited to) are, add_cap add_role get_role map_meta_cap remove_cap remove_role As well as numerous other user related functions that will allow you to verify/validate their authority based upon your use-case scenario and so on. Looking in wp-includes/capabilities.php you we can … Read more

Is it useful to turn on MySQL query cache for performance

General speaking yes for read-only applications (until MySQL 5.7, it’s deprecated since version 8.0), it enables equal SELECTs to return data extremely fast if identical calls are already stored in cache. You should consider that: Only exact same clauses can benefit from the cache engine (no spaces, no comments, no actual differences in WHERE expressions); … Read more