从具有条件和来自另一个表的顺序的表中选择DISTINCT - PHP

Question

我有一个名为table_a的表：

|id |family   |gender   |stock
 1   bag       man       20
 2   bag       woman     23
 3   clothing  child     4
 4   shoe      man       0
 5   shoe      child     3
 6   bag       unissex   34
 7   bag       child     0

另一个名为table_b的表：

|id |gender
 1   man
 2   woman
 3   child
 4   unissex

我如何正确编码以下查询：SELECT DISTINCT gender FROM table_a WHERE family = 'bag' AND stock > '0' ORDER BY table_b.id ASC以便结果如下：[＆＃39; man＆＃39;，＆＃39; woman＆＃39;，＆＃39; unissex＆＃39 ]。不管结果是什么，我希望得到的数组总是具有相同的顺序，＆＃39; man＆＃39;首先，＆＃39;女人＆＃39;在第二个等等，如果＆＃39; man＆＃39;那不是一个结果，而女人＆＃39;来到第一，等等...

Answer 1

使用您当前的结构，您需要加入表格：

SELECT table_a.gender 
FROM table_a JOIN table_b ON table_a.gender=table_b.gender
WHERE table_a.family = 'bag' AND table_a.stock > 0 
GROUP BY table_a.gender
ORDER BY table_b.id

Answer 2

使用 ORDER BY FIELD

指定订单

SELECT DISTINCT gender FROM table_a 
WHERE family = 'bag' AND stock > '0' 
 ORDER BY FIELD(gender,'man','woman','child', 'unissex')

它适用于MySQL