鍍金池/ 問答/數(shù)據(jù)庫/ mysql 這樣的sql語句如何寫,在線求解, 算是字段映射嗎

mysql 這樣的sql語句如何寫,在線求解, 算是字段映射嗎

最近學(xué)習(xí)mysql中, 打算用的一個即時聊天系統(tǒng)練手, 下面一個是用戶名,一個信息表
users表,結(jié)構(gòu)數(shù)據(jù)如圖
clipboard.png
msgs表,結(jié)構(gòu)數(shù)據(jù)如圖

clipboard.png

如何得到圖2的結(jié)果集呢,
圖1
clipboard.png
圖2

clipboard.png

感謝大神的解答, 答案如下

SELECT b.id as '用戶ID' ,b.alias as '用戶昵稱' ,a.fromId as '發(fā)件人id',b.alias as '發(fā)件人昵稱',a.toId as '收件人id',
c.alias as '收件人昵稱', a.content as '發(fā)送內(nèi)容'
FROM msgs as a
INNER JOIN users as b
ON a.fromId = b.id
INNER JOIN users as c
回答
編輯回答
喵小咪

SELECT b.id as '用戶ID' ,b.alias as '用戶昵稱' ,a.fromId as '發(fā)件人id',b.alias as '發(fā)件人昵稱',a.toId as '收件人id',
c.alias as '收件人昵稱', a.content as '發(fā)送內(nèi)容'
FROM msgs as a
INNER JOIN users as b
ON a.fromId = b.id
INNER JOIN users as c
ON a.toId = c.id

clipboard.png

2017年2月13日 06:24