关键字组附近的语法不正确

Question

您好我正在编写一个SQL查询但是我在GROUP BY的行上遇到语法错误.可能是什么问题.

SELECT au_lname, au_fname, t.title_id
from authors As a INNER JOIN
titleauthor As ta On a.au_id = ta.au_id INNER JOIN
titles As t On t.title_id = ta.title_id
ORDER BY au_lname, au_fname
GROUP BY au_lname

Answer 1

在ORDER BY之前放置GROUP BY.此外,select中包含的所有字段必须位于GROUP BY语句中,或者位于聚合函数内.

试试这个:

SELECT au_lname, au_fname, t.title_id
from authors As a INNER JOIN
titleauthor As ta On a.au_id = ta.au_id INNER JOIN
titles As t On t.title_id = ta.title_id
GROUP BY au_lname, au_fname, t.title_id
ORDER BY au_lname, au_fname

如果您只想删除重复的结果,还可以使用关键字DISTINCT:

SELECT DISTINCT au_lname, au_fname, t.title_id
from authors As a INNER JOIN
titleauthor As ta On a.au_id = ta.au_id INNER JOIN
titles As t On t.title_id = ta.title_id
ORDER BY au_lname, au_fname