我有三张桌子。
地点
ID | NAME | TYPE | 1 | add1 | stat | 2 | add2 | coun | 3 | add3 | coun | 4 | add4 | coun | 5 | add5 | stat |
学校
ID | NAME 1 | sch1 2 | sch2 3 |sch3
school_locations
ID |LOCATIONS_ID |SCHOOL_ID 1 | 1 |1 2 | 2 |2 3 | 3 |3
此处的表位置包含应用程序的所有位置。学校的位置由ID调用。
当我使用查询
select locations.name from locations where type="coun";
它显示“ coun”类型的名称
但我想显示location.name,其中只有school_locations的类型为“ coun”
我尝试了以下查询,但似乎都没有用
select locations.name from locations where type="coun" inner join school_locations on locations.id=school_locations.location_id inner join schools on school_locations.school.id=schools.id;
和
select locations.name from locations inner join school_locations on locations.id=school_locations.location_id inner join schools on school_locations.school.id=schools.id where type="coun";
是否可以在查询中使用多个内部联接,还是有另一种方法?
SELECT `locations`.`name` FROM `locations` INNER JOIN `school_locations` ON `locations`.`id` = `school_locations`.`location_id` INNER JOIN `schools` ON `school_locations`.`school_id` = `schools_id` WHERE `type` = 'coun';
该WHERE子句必须在语句的末尾
WHERE