WordPress mu-plugin to add support for "title_like" in WP_Query to add a LIKE WHERE clause to a query.

wp-title-like-where.php

<?php
/**
 * Example usage to find all Titles with a comma:
 * $example_query = new WP_Query(
 *   array(
 *     'title_like' => ','
 *   )
 * );
 */

add_filter( 'posts_where', 'fe_title_like_where', 10, 2 );
function fe_title_like_where( $where, &$wp_query ) {
  global $wpdb;
	if ( $title_like = $wp_query->get( 'title_like' ) ) {
    $where .= ' AND ' . $wpdb->posts . '.post_title LIKE \'%' . $wpdb->esc_like( $title_like ) . '%\'';
  }
  return $where;
}