我有一个mySQL查询来处理WordPress中相当复杂的搜索，因为我一直在努力让wp_query做我需要的所有事情。
然而，有时查询需要很长时间才能运行（有时10秒以上！）有时它似乎只是使服务器崩溃（媒体模板网格），返回internal server error或Error establishing database connection
我不确定查询中是否存在导致其崩溃的常规语法错误，但实际上生成查询的PHP看起来像这样：
<?php
// declare wordpress database global
global $wpdb;
// order by option
$order = $_SESSION['search']['sort-by'];
// users lat, long and distance preferences
$lat = $_SESSION['search']['lat'];
$long = $_SESSION['search']['long'];
$radius = $_SESSION['search']['distance'];
// user search start/end date
$startDate = date('Ymd', strtotime($_SESSION['search']['from']));
$endDate = date('Ymd', strtotime($_SESSION['search']['to']));
// get the main category search ID
$maincat = get_term_by( 'slug', $_SESSION['search']['cat'], 'main-cat');
$maincat = $maincat->term_taxonomy_id;
// grab keywords, replace special chars and spaces
$keywords = $_SESSION['search']['keyword'];
$keywords = preg_replace('/[^A-Za-z0-9 ,]/u','', strip_tags($keywords));
$keywords = str_replace(' ', '', $keywords);
// put keywords into array
$subcatItems = explode(',', $keywords);
$keywords = $subcatItems;
// for each keywords get the sub category id's
$subcats = array();
$count = count($subcatItems) - 2;
for ($i = 0; $i <= $count; $i++) {
$subcatItems[$i] = get_term_by( 'slug', $subcatItems[$i], 'sub-cat');
if ($subcatItems[$i] != '') :
$subcatItems[$i] = $subcatItems[$i]->term_taxonomy_id;
array_push($subcats, $subcatItems[$i]);
endif;
}
if( $subcats != '' ) :
$subcats = implode(',', $subcats);
endif;
// select
$query = 'SELECT SQL_CALC_FOUND_ROWS wp_posts.*, ';
// geo locate
$query .= '( 3959 * acos(
cos( radians('.$lat.') )
* cos( radians( lat ) )
* cos( radians( lng ) - radians('.$long.') )
+ sin( radians('.$lat.') )
* sin( radians( lat ) )
) )
AS distance , lat AS latitude , lng AS longitude ';
// from
$query .= 'FROM wp_posts ';
// inner joins
$query .= 'INNER JOIN wp_term_relationships ON (wp_posts.ID = wp_term_relationships.object_id) ';
if ( $keywords != '' ) :
$query .= 'INNER JOIN wp_term_relationships AS tt1 ON (wp_posts.ID = tt1.object_id) ';
endif;
$query .= 'INNER JOIN wp_postmeta ON (wp_posts.ID = wp_postmeta.post_id) ';
$query .= 'INNER JOIN wp_postmeta AS mt1 ON (wp_posts.ID = mt1.post_id) ';
// if ordered by price, join post meta again
if( $order == 'mt2.meta_value+0' ) :
$query .= 'INNER JOIN wp_postmeta AS mt2 ON (wp_posts.ID = mt2.post_id) ';
endif;
// if there are keywords
if ( $keywords != '' ) :
$query .= 'INNER JOIN wp_postmeta AS mt3 ON (wp_posts.ID = mt3.post_id) ';
endif;
// join table to geo locate
$query .= 'INNER JOIN lat_lng_post ON wp_posts.ID = lat_lng_post.post_id ';
// basic filter
$query .= 'WHERE 1=1 ';
$query .= 'AND wp_posts.post_type = "event" ';
$query .= 'AND wp_posts.post_status = "publish" ';
// geo filter
$query .= 'AND lat_lng_post.lat = lat ';
$query .= 'AND lat_lng_post.lng = lng ';
// date filter
$query .= 'AND ( ';
$query .= '(wp_postmeta.meta_key LIKE "date_%_start-date" AND CAST(wp_postmeta.meta_value AS SIGNED) <= "'.$endDate.'") ';
$query .= 'AND (mt1.meta_key LIKE "date_%_end-date" AND CAST(mt1.meta_value AS SIGNED) >= "'.$startDate.'") ';
$query .= 'AND substr(wp_postmeta.meta_key, 1, 6) = substr(mt1.meta_key, 1, 6) ';
$query .= ') ';
// taxonomies filter
$query .= 'AND ( wp_term_relationships.term_taxonomy_id IN ('.$maincat.') ) ';
// if keywords
if ( $_SESSION['search']['keyword'] != '' ) :
$query .= 'AND ( ';
// for each keyword, and a statement to check post title
$keywordCount = 0;
foreach ( $keywords as $keyword ) :
if( $keyword != '' ) :
if( $keywordCount == 0 ) :
$query .= '(wp_posts.post_title LIKE "%'.$keyword.'%") ';
else :
$query .= 'OR (wp_posts.post_title LIKE "%'.$keyword.'%") ';
endif;
endif;
$keywordCount++;
endforeach;
// for each keyword, and a statement to check description
foreach ( $keywords as $keyword ) :
if( $keyword != '' ) :
$query .= 'OR (mt3.meta_key = "description" AND mt3.meta_value LIKE "%'.$keyword.'%") ';
endif;
endforeach;
// for each keyword, and a statement to check sub category taxonomy
if( $subcats != '' ) :
$query .= 'OR ( tt1.term_taxonomy_id IN ('.$subcats.') )';
endif;
$query .= ') ';
endif;
// if ordered by adult
if( $order == 'mt2.meta_value+0' ) :
$query .= 'AND mt2.meta_key = "adult" ';
endif;
// grouping and sorting
$query .= 'GROUP BY wp_posts.ID ';
$query .= 'HAVING distance <= '.$radius.' ';
$query .= 'ORDER BY '.$order.' ASC ';
$query .= 'LIMIT 0, 10';
$events = $wpdb->get_results( $query, 'OBJECT' );
?>
如果有人有任何想法，请告诉我！如果您需要更多信息，我很乐意提供：）
修改
当搜索中存在关键字时，查询似乎更加困难。我不确定是否有更好的方法来编写逻辑：
if ( $_SESSION['search']['keyword'] != '' ) :
$query .= 'AND ( ';
// for each keyword, and a statement to check post title
$keywordCount = 0;
foreach ( $keywords as $keyword ) :
if( $keyword != '' ) :
if( $keywordCount == 0 ) :
$query .= '(wp_posts.post_title LIKE "%'.$keyword.'%") ';
else :
$query .= 'OR (wp_posts.post_title LIKE "%'.$keyword.'%") ';
endif;
endif;
$keywordCount++;
endforeach;
// for each keyword, and a statement to check description
foreach ( $keywords as $keyword ) :
if( $keyword != '' ) :
$query .= 'OR (mt3.meta_key = "description" AND mt3.meta_value LIKE "%'.$keyword.'%") ';
endif;
endforeach;
// for each keyword, and a statement to check sub category taxonomy
if( $subcats != '' ) :
$query .= 'OR ( tt1.term_taxonomy_id IN ('.$subcats.') )';
endif;
$query .= ') ';
endif;
编辑2
我刚才有另外一个想法，将查询拆分成单独的查询会更快吗？那么首先完成地理查询，获取那些帖子ID并进行日期查询，然后再进行关键字查询？我对mySQL很新，所以不太清楚如何优化它：/
答案 0 :(得分：2)
尝试将最终条件添加到连接（多个连接条件）。
如果你在连接处使用多个条件而不是获得一个庞大的设置然后将条件设置在最后，那么你的设置会更小，你的响应时间可能会更好。
例如，你有最终条件：AND wp_posts.post_type = "event"
你可以把它放在第一次加入
中INNER JOIN wp_term_relationships ON (wp_posts.ID = wp_term_relationships.object_id) AND wp_posts.post_type = "event"
INNER JOIN...
等等。