我对一个例子感到困惑from the docs:

<?php
    // The main query.
    if ( have_posts() ) : while ( have_posts() ) : the_post();
        the_title();                                                             
        the_content();                                                          
    endwhile;                                                                   
    else :                                                                      
        // When no posts are found, output this text.                           
        _e( \'Sorry, no posts matched your criteria.\' );                         
    endif;                                                                       
    wp_reset_postdata();                                                        

    /*                                                                          
     * The secondary query. Note that you can use any category name here. In our example,
     * we use "example-category".                                               
     */                                                                        
    $secondary_query = new WP_Query( \'category_name=example-category\' );        

    // The second loop. if ( $secondary_query->have_posts() ) 
    echo \'<ul>\';
    while ( $secondary_query->have_posts() ) :
        $secondary_query->the_post();
        echo \'<li>\' . get_the_title() . \'</li>\';
    endwhile;
    echo \'</ul>\';
    endif;
wp_reset_postdata();
?>

不是第一个wp_reset_postdata() 完全冗余？查询前$post, 二次查询无论如何都会覆盖它，对吗？是否有过打电话有意义的情况wp_reset_postdata() 在主回路之后？

if ( $arg ) :
    // loop
    wp_reset_postdata();
else :
    // no results
endif;