sql - add_filter function not working as expected -

i'm trying edit wp_query in wordpress using add_filter function. when var_dump query request outputs sql expected.

however, when runs returns error different query! know why query might change, , change much!

query request var_dump (as expected):

select sql_calc_found_rows  wp_posts.*,      ( 3959 * acos(          cos( radians(52.486243) )           * cos( radians( lat ) )           * cos( radians( lng ) - radians(-1.890401) )           + sin( radians(52.486243) )           * sin( radians( lat ) )           ) )       distance , lat  latitude , lng longitude  wp_posts   inner join wp_term_relationships on (wp_posts.id = wp_term_relationships.object_id)  inner join wp_postmeta on (wp_posts.id = wp_postmeta.post_id) inner join wp_postmeta mt1 on (wp_posts.id = mt1.post_id)  inner join lat_lng_post on wp_posts.id = lat_lng_post.post_id  1=1   , ( wp_term_relationships.term_taxonomy_id in (2) )  , wp_posts.post_type = 'event'  , ((wp_posts.post_status = 'publish'))  , ( (wp_postmeta.meta_key 'date_%_start-date' , cast(wp_postmeta.meta_value signed) <= '20140704') ,  (mt1.meta_key 'date_%_end-date' , cast(mt1.meta_value signed) >= '20140627') )  , lat_lng_post.lat = lat  , lat_lng_post.lng = lng  , substr(wp_postmeta.meta_key, 1, 6) = substr(mt1.meta_key, 1, 6)   group wp_posts.id  having distance <= 20  order distance asc  limit 0, 10 

and query shows below error [unknown column 'lat' in 'field list'] (not expected):

select wp_posts.*,      ( 3959 * acos(          cos( radians(52.486243) )          * cos( radians( lat ) )          * cos( radians( lng ) - radians(-1.890401) )          + sin( radians(52.486243) )          * sin( radians( lat ) )       ) ) distance , lat latitude , lng longitude  wp_posts  1=1  , wp_posts.post_type = 'acf-field'  , ((wp_posts.post_status = 'publish'))  , wp_posts.post_name = 'field_535e6b9ffe3da'  , lat_lng_post.lat = lat  , lat_lng_post.lng = lng  group wp_posts.id  having distance <= 20  order distance asc  limit 0, 1 

note

i have custom table called lat_lng_post has 3 columns, post_id, lat, lng store location data each event (custom post type).

edit add_filter functions being used on query:

function distance_query($distance) {      $lat = $_session['search']['lat'];     $lng = $_session['search']['long'];       $distance .= ",      ( 3959 * acos(          cos( radians(".$lat.") )           * cos( radians( lat ) )           * cos( radians( lng ) - radians(".$lng.") )           + sin( radians(".$lat.") )           * sin( radians( lat ) )           ) )       distance , lat  latitude , lng longitude";     return $distance; } add_filter('posts_fields', 'distance_query');    // add lat_lng_post table inner join function lat_lng_join($join) {     $join = str_replace('(wp_posts.id = mt1.post_id)', '(wp_posts.id = mt1.post_id) inner join lat_lng_post on wp_posts.id = lat_lng_post.post_id', $join);     return $join; } add_filter('posts_join', 'lat_lng_join');   // set lat lng definition function lat_lng_define($define) {     $define .= ' , lat_lng_post.lat = lat , lat_lng_post.lng = lng';     return $define; } add_filter('posts_where', 'lat_lng_define');   // having distance less user distance function having_distance($having) {     $radius = $_session['search']['distance'];     $having = 'wp_posts.id having distance <= '.$radius.'';     return $having; } add_filter('posts_groupby', 'having_distance');  // if sorting distance function sort_distance($sortdistance) {     $sortdistance = 'distance asc';     return $sortdistance; } if( $_session['search']['sort-by'] == 'distance' ) :     add_filter('posts_orderby', 'sort_distance'); endif;   function add_additional_where_condition($where) {     $where .= " , substr(wp_postmeta.meta_key, 1, 6) = substr(mt1.meta_key, 1, 6) ";     return $where; }  // fix setting date search field function date_to( $to ) {     $to = str_replace("mt1.meta_key = 'date_%_end-date'", "mt1.meta_key 'date_%_end-date'", $to);     return $to; }  // fix setting date search field    function date_from( $from ) {     $from = str_replace("meta_key = 'date_%_start-date'", "meta_key 'date_%_start-date'", $from);     return $from; }  // fix ordering date function order_date( $like ) {     $like = str_replace("mt2.meta_key = 'date_%_end-date'", "mt2.meta_key 'date_%_end-date'", $like);     return $like; }  // fix searching post title, requires characters match  function title_filter( $where, &$wp_query ) {     global $wpdb;     if ( $search_term = $wp_query->get( 'title_like' ) ) {         $where .= ' , ' . $wpdb->posts . '.post_title \'%' . esc_sql( like_escape( $search_term ) ) . '%\'';     }     return $where; } 

also, wp_query these functions being added to:

// add query title     add_filter( 'posts_where', 'title_filter', 10, 2 );  // dates , logic     add_filter('posts_where', 'date_from');     add_filter('posts_where', 'date_to');     add_filter('posts_where', 'order_date');     add_filter('posts_where', 'add_additional_where_condition');   // date inputs search     $date1 = str_replace('/', '-', $_session['search']['from']);     $when = date("ymd", strtotime($date1));      $date2 = str_replace('/', '-', $_session['search']['to']);     $when2 = date("ymd", strtotime($date2));      $year = date('y');     // declare query arguments      if ( get_query_var('paged') ) {          $paged = get_query_var('paged');      } else if ( get_query_var('page') ) {         $paged = get_query_var('page');      } else {         $paged = 1;      }  // make keywords array     $keywordstring = $_session['search']['keyword'];     $keywords = explode(', ', $keywordstring);      $taxquery = array(         'relation' => 'and',         array (             'taxonomy' => 'main-cat',             'field' => 'slug',             'terms' => $_session['search']['cat']         )     );      if( $_session['search']['keyword'] != '' ) {         $taxquery[] = array(             'taxonomy' => 'sub-cat',             'field' => 'name',             'terms' => $keywords         );     }      $args = array(         // general         'post_type' => 'event',         'post_status' => 'publish',         'posts_per_page' => 10,         'paged' => $paged,         'cache_results' => false,         'update_post_meta_cache' => false,         'update_post_term_cache' => false,          'meta_key' => $_session['search']['sort-key'],         'orderby' => $_session['search']['sort-by'],         'order' => 'asc',          // category filter         'tax_query' => $taxquery,          // date filter          'meta_query' => array(             'relation' => 'and',             array(                 'key' => 'date_%_start-date',                 'value' => $when2,                 'compare' => '<=',                 'type' => 'numeric'             ),             array (                 'key' => 'date_%_end-date',                 'value' => $when,                 'compare' => '>=',                 'type' => 'numeric'             )          )     );       $temp = $wp_query;     $wp_query = null;     $wp_query = new wp_query( $args ); 

it looks you're trying setup posts_* filters secondary query, forget remove filters afterwards, affecting other queries run later.

i) can remove filter remove_filter() function. here's example :

// add filter: add_filter( 'some_filter', 'some_filter_callback', $priority );  // run secondary query: $wp_query = new wp_query( $args );  // remove previous filter: remove_filter( 'some_filter', 'some_filter_callback', $priority ); 

where filter priority must match.

ii) way use add remove_filter() inside some_filter_callback() function. example:

add_filter( 'some_filter', 'some_filter_callback' ); $wp_query = new wp_query( $args ); 

where

some_filter_callback( $string ) {     // remove current filter:     remove_filter( current_filter(), __function__ );      // modifications input:     // ...      // output:     return $string; } 

this make sure filter run once.

iii) if you're trying modify main query, can restrict filter with:

if( ! is_admin() && is_main_query() ) {      // ... } 

or

if( ! is_admin() && $query->is_main_query() ) {      // ... } 

if you're using pre_get_posts hook, $query input argument.

iv) option create new class extends wp_query , contains filters want:

class my_search_query extends wp_query {    // ... } 

where use

$query = new my_search_query( $args ); 

to run query.