Drupal 7 db_select嵌套選擇查詢

Question

如何將嵌套的select查詢轉換爲Drual 7 db_select？以下是問題查詢：

select 
    * 
from 
    tbl_word 
where 
    EngWord like '%apple%' or 
    WordID in (
     select 
      WordID 
     from 
      tbl_subword 
     where 
      EngWord like '%apple%' 
    ); 

Answer 1

語義上它是非常simliar：

$term = 'apple'; 

$sub_query = db_select('tbl_subword') 
    ->fields('tbl_subword', array('WordID')) 
    ->condition('EngWord', '%' . db_like($term) . '%'), 'LIKE'); 

$query = db_select('tbl_word') 
    ->fields('tbl_word') 
    ->condition(db_or() 
    ->condition('EngWord', '%' . db_like($term) . '%', 'LIKE') 
    ->condition('WordID', $sub_query, 'IN') 
); 

$results = $query->execute()->fetchAll();