Query all wordpress post titles - php

Question

I am using Wordpress auto suggests using this snippet of code
and currently it is searching all tags, I want it to search only post titles. Any help is appreciated.
This is sql query calling all the tags which needs to be modified for all posts.
<?php global $wpdb;
$search_tags = $wpdb->get_results("SELECT name from wp_terms WHERE name LIKE '$search%'");
foreach ($search_tags as $mytag)
{
echo $mytag->name. " ";
}
?>

Answer 1

These days i had to do some request in a wordpress theme.
In your case ( getting title can be done easier than getting tags, as in your example link ) the stuff can be done easier (i guess).
Firstly you have to make a php page to get posts. As you maybe know you won't be able to use wp stuff in standalone php files, so your file ( let call it get_posts.php ) will look like
<?php
// Include the file above for being able to use php stuff
// In my case this file was in a folder inside my theme ( my_theme/custom_stuff/get_posts.php ).
// According to this file position you can modify below path to achieve wp-blog-header.php from wp root folder
include( '../../../../wp-blog-header.php' );
// Get all published posts.
$list_posts = get_posts( array( 'numberposts' => -1 ) );
// Get "q" parameter from plugin
$typing = strtolower( $_GET["q"] );
//Save all titles
$list_titles = array();
foreach( $list_posts as $post ) { $list_titles[] = $post->post_title; }
// To see more about this part check search.php from example
foreach( $list_titles as $title ) {
if( strpos( strtolower( $title ), $typing ) ){
echo $title;
}
}
?>
I added some comments trying to help you better.
Now stuff get easy, you only have to call your page through jQuery plugin like
$('#yourInput').autocomplete( "path_to/get_posts.php" );

Answer 2

You can directly use wordpress in-build feature to get all post titles
// The Query
query_posts( 'posts_per_page=-1' );
// The Loop
while ( have_posts() ) : the_post();
echo '<li>';
the_title();
echo '</li>';
endwhile;

Answer 3

None of the answers here answer your real question:
How to query JUST post titles
The "raw SQL" way:
Few important things:
escape search for SQL! (also do that for the tags search!) use $GLOBALS['wpdb']->esc_like()
if you only need 1 column, you can use $GLOBALS['wpdb']->get_col()$GLOBALS['wpdb']->get_results() is if you want to fetch more columns in one row
use $GLOBALS['wpdb']->tableBaseName to make your code portable - takes care of the prefixe.g. $GLOBALS['wpdb']->posts
When querying posts you must also think about which post_type and post_status you want to query=> usually the post_status you want ispublish, but post_type may vary based on what you want
WordPress table "posts" contains ALL post types - post, page, custom, but also navigation, contact forms etc. could be there! => I strongly advice to use explicit post_type condition(s) in WHERE ! :)
...$GLOBALS is same as globalizing variabl -today performance difference is little
<?php
// to get ALL published post titles of ALL post types (posts, pages, custom post types, ...
$search_post_titles = $GLOBALS['wpdb']->get_col(
"SELECT post_title from {$GLOBALS['wpdb']->posts}
WHERE (
(post_status = 'publish')
AND
(post_title LIKE '{$GLOBALS['wpdb']->esc_like($search)}%')
)
ORDER BY post_title ASC
"); // I also added ordering by title (ascending)
// to only get post titles of Posts(Blog)
// you would add this to conditions inside the WHERE()
// AND (post_type = 'post')
// for Posts&Pages
// AND ((post_type = 'post') OR (post_type = 'page'))
// test output:
foreach ($search_post_titles as $my_title) {
echo $my_title . " ";
}
?>
The WP_Query way
This is more wordpress but has a little overhead, because although there is a fields param for new WP_Query()/get_posts(), it only has options:
'all' - all fields (also default), 'ids' - just ids, 'id=>parent' - ... if you pass anything else, you still get all, so you still need to add "all" BUT - WP however has filters for altering fields in SELECT.
I tried to make it the same as the raw SQL version, but it depends on how does WP does it's "search" - which I think is %search% for 1 word + some more logic if there are more words. You could leverage the $clauses filter used for fields to also add your custom where INSTEAD of adding the 's' into $args (remember to append to not-lose existing WHEREs $clauses['where' .= "AND ...;). Also post_type => 'any' does not produce always the same results as the raw query in cases like Navigation, Contact forms etc...
Also WP_Query sanitizes the input variables so actually don't escape $args!
<?php
$args = [
'fields' => 'all', // must give all here and filter SELECT(fields) clause later!
'posts_per_page' => -1, // -1 == get all
'post_status' => 'publish',
's' => $search,
// I also added ordering by title (ascending):
'orderby' => 'title',
'order' => 'ASC',
'post_type' => 'any', // all "normal" post types
// 'post_type' => 'post', // only "blog" Posts
// 'post_type' => ['post', 'page'], // only blog Posts & Pages
];
$onlyTitlesFilter = function($clauses, $query) {
// "fields" overrides the column list after "SELECT" in query
$clauses['fields'] = "{$GLOBALS['wpdb']->posts}.post_title";
return $clauses; // !FILTER! MUST RETURN!
};
$onlyTitlesFilterPriority = 999;
// add filter only for this query
add_filter('posts_clauses', $onlyTitlesFilter, $onlyTitlesFilterPriority, 2);
// Pro-tip: don't use variable names like $post, $posts - they conflict with WP globals!
$my_posts = (new WP_Query($args))->get_posts();
// !IMPORTANT!
// !remove the filter right after so we don't affect other queries!
remove_filter('posts_clauses', $onlyTitlesFilter, $onlyTitlesFilterPriority);
// test output:
// note that I used "my"_post NOT just $post (that's a global!)
foreach($my_posts as $my_post) {
echo $my_post->post_title . " ";
}
?>
Don't be confused - you will still get the array of WP_Posts - WP will throw some default properties&values into it, but in reality it will only query and fill-in with real values the fields you specify in the filter.
PS: I've tested these - they are working codes (at least on WP 5.4 and PHP7 :) )