我一直得到重复的结果

Question

我是SQL新手，我使用Oracle Apex。我正在尝试运行以下查询：

Select COMPANIES.COMP_NO as "Company Id", COMP_NAME as Company",
OPEN_START_DATE as "Start Date", OPEN_TITLE as "Opening Title", 
QF_CODE as "Required Qualification" 
From OPENINGS, COMPANIES
Where COMP_ADDRESS='Auckland'
AND OPEN_START_DATE Between '12/01/2016' AND '12/31/2016';

我知道应该只有四个返回的结果，但我不断获得相同条目的重复。我究竟做错了什么？？我相信它必须与我的表连接有关...谢谢

Answer 1

select 
    c.comp_no,
    c.comp_name,
    o.start_date,
    o.open_title 
from 
    companies c 
    join openings o on o.comp_no=c.comp_no 
where 
    start_date between '2016-10-01' and '2016-10-07';

使用join而不是在from子句中选择它。