可以从具有特定信息的两个表中获取数据的Mysql查询

Question

问题在于我的查询。我需要从两个表中选择数据，table1有一个字段类别，它是类别id，table2有字段id，它是类别id。我需要按月选择数据，例如，如果我们选择2月份，我会在选定的时间段内对该表中的所有内容进行计数，并按类别ID进行分组。例如，在table1中的选定月份中，没有类别id = 3，十个从table2获取并使该类别值= 0。如果在table1的March期间是id = 3的类别，则计算具有该类别id的所有值。

我做了一个选择，但它不对。

$query = sprintf("SELECT count(*) as counter, category, (select category from categories where id=leads.category) as categoryname, clientcode , language                   
                  FROM leads   
                  WHERE synced > %s and synced < %s
                  GROUP BY category, clientcode 
               UNION ALL
                  SELECT 0 as counter, id as category, category as categoryname, 0 as clientcode, language  FROM categories WHERE id NOT IN(SELECT category FROM leads)
                  GROUP BY category, clientcode ",$starttime, $endtime ); 

感谢您的帮助，希望您了解我的需求。

很多文字......

我解决了这个问题：

$query = sprintf("SELECT count(*) as counter, category, (select category from categories where id=leads.category) as categoryname, clientcode , language                   
                      FROM leads   
                      WHERE synced > %s and synced < %s
                      GROUP BY category, clientcode 
                   UNION ALL
                      SELECT 0 as counter, id as category, category as categoryname, 0 as clientcode, language  FROM categories WHERE id NOT IN(SELECT category FROM leads WHERE synced > %s and synced < %s)
                      GROUP BY category, clientcode ",$starttime, $endtime, $starttime, $endtime );