Question

我有这张桌子


    CREATE TABLE title
    (`id` int, `title` varchar(16), `author` varchar(6), `city` varchar(8), `year` int, `pageId` varchar(4), `page` int);

   INSERT INTO title
       (`id`, `title`, `year`, `pageId`, `page`)
   VALUES
       (1, 'A', 1951, '20', 1),
       (2, 'A',  1951, '99', 2),
       (3, 'A',  1951, '101', 3),
       (4, 'A',  1951, NULL, 4),
       (5, 'B',  1937, '200', 76),
       (6, 'B',  1937, '201', 73),

       (7, 'C',  1951, '4', 32),
       (8, 'C',  1951, NULL, 32),

    (9, 'D',  1937, '6', 74)
;

我需要选择ID＃6和＃9

选择标题分组，如果在任何记录中pageId不为空

Answer 1

尝试一下

SELECT 
   t1.id, t1.title, t1.year, t1.pageId, t1.page
  FROM 
   title t1
  WHERE 
    t1.pageId IS NOT NULL AND (t1.id = 6 OR t1.id = 9) 
  GROUP BY t1.title

MySQL选择分组依据且不为空

1 个答案: