多维度mysqlselect?
multi dimensional mysql select?
table: car_profile
carid, carname, caryear, cartype
table: user_profile
userid, username, useremail
table: user_car
id, carid, userid, status
FC: carid, userid
一个carid
可以有多个userid
在tableuser_car
(一辆车可以多人使用)
给定一个carid
,我想selectcaryear
、cartype
、[userid, username, useremail]
。括号内的那个本身应该是一个数组,因为多个 userid
是可能的。我不确定这是否可行?
SELECT 可以 return 单个值、一行值或 table 行。没有更高维度的选择。下面,多个 userid
、username
、useremail
将显示在不同的行中。
SELECT cp.caryear, cp.cartype, up.userid, up.username, up.useremail
FROM car_profile as cp
LEFT JOIN user_car as uc
ON uc.carid = cp.carid
LEFT JOIN user_profile as up
ON uc.userid = up.userid
WHERE cp.carid = carid
ORDER BY cp.caryear, cp.cartype
table: car_profile
carid, carname, caryear, cartype
table: user_profile
userid, username, useremail
table: user_car
id, carid, userid, status
FC: carid, userid
一个carid
可以有多个userid
在tableuser_car
(一辆车可以多人使用)
给定一个carid
,我想selectcaryear
、cartype
、[userid, username, useremail]
。括号内的那个本身应该是一个数组,因为多个 userid
是可能的。我不确定这是否可行?
SELECT 可以 return 单个值、一行值或 table 行。没有更高维度的选择。下面,多个 userid
、username
、useremail
将显示在不同的行中。
SELECT cp.caryear, cp.cartype, up.userid, up.username, up.useremail
FROM car_profile as cp
LEFT JOIN user_car as uc
ON uc.carid = cp.carid
LEFT JOIN user_profile as up
ON uc.userid = up.userid
WHERE cp.carid = carid
ORDER BY cp.caryear, cp.cartype