我有一個表中的字段包含整數或NULL。 parent_id
2
4
6
NULL
NULL
45
2
我怎麼會去添加IFNULL語句,以便ans_count將0代替NULL來填充? 這裏是我的SQL代碼: ...
(SELECT parent_id AS pid, COUNT(*) AS ans_count
FROM qa
GROUP BY parent_i
SELECT 'id' FROM `table` WHERE `id` =
(select min(`id`) FROM `table` where
`id` < 1 and `ids` = 1)
id ids
1 1
2 1
5 1
6 1
結果: id = ''
我需要改變id=''到id='n/a'
我想用一個基於連接表的值的查詢來查詢幾個表。 SELECT a.id,a.name,
IFNULL(b.imageurl, 'default image url') AS 'imageurl',
IFNULL(b.imagecategory, '34') AS 'imagecategory',
IFNULL(b.imagetype, 't') AS 'imagetype'
FROM sum
我有一個查詢得到的值(這是相當長的,但這裏是它的要點)
Name.find_by_sql(['SELECT IFNULL(users.last_name, "nil") FROM users
JOIN user_groups ON user_groups.user_id = users.id
JOIN groups ON groups.id = user_g
IFNULL功能似乎並不爲我工作工作....當我執行此查詢 select t1.dAccHeader_id,t1.dAccHeaderName,t1.dAccHeaderAcronym,
t2.dDesignationName as incharge1,
t3.dDesignationName as incharge2,t4.dDesignationName as incharge3
fro