Problem on displaying the results on my query

Question

Hello this is my query. I want to show the titles of posts that have fullfil the following but it doesn't show anything, I don't know. Thank you! Also, is there another way to show the results, more wordpress-like?

<?php 

$theposts = $wpdb->get_results("SELECT post_title FROM $wpdb->posts
    WHERE ID IN
(
   SELECT DISTINCT post_id
   FROM $wpdb->postmeta
   WHERE meta_key = 'extra1' AND meta_value = 'test'
)");

foreach ($theposts as $thepost) {
echo $thepost->post_title;

}
?>

Answer 1

You need to use WordPress meta query:

Display posts where the custom field key is 'extra1' and the custom field value is 'test':

$query = new WP_Query( array( 'meta_key' => 'extra1', 'meta_value' => 'test' ) );

For more info take a look at WP Query Custom_Field_Parameters.