Question

我的相册按ID排序，现在我只想显示专辑B字母。

我的旧查询

$valueql_select="SELECT DISTINCT (i.gallery_album_id) FROM mov_gallery_album AS a, mov_gallery_images AS i WHERE a.gallery_album_id = i.gallery_album_id AND a.gallery_cat_id =".$_GET['cat']." ORDER BY gallery_id desc";

我尝试使用LIKE

$valueql_select="SELECT DISTINCT (i.gallery_album_id) FROM mov_gallery_album AS a, mov_gallery_images AS i WHERE a.gallery_album_id = i.gallery_album_id AND a.gallery_cat_id =".$_GET['cat']." ORDER BY name LIKE 'b%'";

但上述查询不起作用。

Answer 1

将条件放在WHERE子句中：

$valueql_select="SELECT DISTINCT i.gallery_album_id
                 FROM mov_gallery_album AS a
                 JOIN mov_gallery_images AS i
                 ON a.gallery_album_id = i.gallery_album_id
                 WHERE a.gallery_cat_id = '42'
                 AND name LIKE 'b%'
                 ORDER BY name";

此外，您还有SQL注入漏洞。不将值连接到SQL字符串中。特别是当它们直接来自用户输入而没有任何验证时。

相关

How can I prevent SQL injection in PHP?

Answer 2

如果您需要对以B开头的名称进行排序，请首先尝试：

ORDER BY
CASE WHEN name name LIKE 'b%' THEN 0 ELSE 1 END, name ;

如果您希望获得以B开头的名称，则必须将LIKE谓词移动到WHERE子句，如下所示：

WHERE a.gallery_album_id = i.gallery_album_id 
 AND a.gallery_cat_id =".$_GET['cat']."
 AND name LIKE 'b%'
 ORDER BY name

如何使用mysql查询按字母顺序排序

2 个答案: