wpdb - Read For Learn

$wpdb->get_results not returning an array

It has nothing to do with $wpdb. It’s PHP parse error. print_r is a function, so you can’t do print_r $datarow; You should use print_r( $datarow ); instead.

Perform a function when a user clicks register button

You can hook your function with user_register. It will fire immediately after an user registration is done. And user id is passed to hook as an argument. add_action( ‘user_register’, ‘my_custom_function’ ); function my_custom_function ( $user_id ) { //here goes your code }

Ascending order of yearly archives [closed]

You will have to define post order in second SQL query too. Try this one. // get years that have posts $years = $wpdb->get_results( “SELECT YEAR(post_date) AS year FROM wp_posts WHERE post_type=”post” AND post_status=”publish” GROUP BY year DESC” ); foreach ( $years as $year ) { // get posts for each year $posts_this_year = $wpdb->get_results( … Read more

wpquery properties last_query and last_result : should these be public or private?

As you can guess from version number this code is ancient. So ancient in fact that var keyword is from PHP 4 and is deprecated in PHP 5 (considered synonym of public for backwards compatibility). So inline doc hints it is private because back then there was no actual property visibility in PHP language. So … Read more

Exclude specific terms from all queries using posts_where or something similar

My SQL knowledge is quite bad, I should admit, so I’m going to use a non SQL way to achieve this. Here is my idea: Use pre_get_posts to alter the query variables before the main query is executed. As all of the query variable has been set by the time pre_get_posts run, you can simply … Read more

Incorrect Use of wpdb::prepare()

You should try to replace the meta_value = $list->ID part with the placeholder meta_value = %d. Then use the following: $subscriber_count = $wpdb->get_var( $wpdb->prepare( $q, $list->ID ) ); where the input argument $list->ID will be treated as an integer (signed). From the Codex: The query parameter for prepare accepts sprintf()-like placeholders. The %s (string), %d … Read more

Inserting a MySQL record into a table with an array of field names and an array of values

Yes, you can pass an array of values. This is explained in the codex under Protect Queries Against SQL Injection Attacks value_parameter (int|string|array) The value to substitute into the placeholder. Many values may be passed by simply passing more arguments in a sprintf()-like fashion. Alternatively the second argument can be an array containing the values … Read more