表1:如下CREATE TABLE student (sid integer, sname text, age integer);sqlite> select * from student;1|zhang|222|li|213|wang|194|xue|195|zhao|20表2:如下CREATE TABLE achievements (cid integer, sid integer, course text, results integer);2|1|shuxue|854|2|shuxue|906|3|shuxue|828|4|shuxue|7210|5|shuxue|100我要查詢年齡為20的學生的成績該怎么寫連接sql語句???sqlite> select a.results from achievements as a inner join student as s where s.age=20;85908272100為什么上面的語句查出來的不是100這個數,而是把所有的成績全打出來了??正確的語句該怎么寫???
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MM們
TA貢獻1886條經驗 獲得超2個贊
少一個連接條件
select a.results from achievements as a inner join student as s where s.age=20;
改為
select a.results from achievements as a inner join student as s on a.sid = s.sid where s.age=20;
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