我已經得到了下面的表格中進行選擇:MySQL的三個表作爲一個
| table_one | table_two | table_three | table_four |
| t_one_id | t_two_id | t_three_id | t_four_id | // primary key (auto increment)
| | two_nid | three_nid | four_nid | // foreign key to table_one.t_one_id
| tone_date | ttwo_date | tthree_date | tfour_date | // time this was posted.
// other fields
而下面的查詢,
SELECT `table_two` . * , `table_three` . * , `table_four` . *
FROM `table_two`
JOIN (`table_three`) ON `table_three`.`three_nid`=1
JOIN (`table_four` ) ON table_four`.`four_nid`=1
WHERE `table_two`.`two_nid`=1
,後面的數據:
table_one: 1, 11/08/2011
table_two: 1, 1, 12/08/2011
table_three: 1, 1, 13/08/2011
table_four: 1, 1, 14/08/2011
現在我的查詢不斷返回零結果,即使如此,但我期待它返回的是(當在每個表的日期排序):
result 1: 1 | 1 | 12/08/2011 | // this is from table_two
result 2: 1 | 1 | 13/08/2011 | // from table three
result 2: 1 | 1 | 14/08/2011 | // from four
我也曾嘗試以下,但沒有成功:
SELECT * FROM table_two t2, table_three t3, table_four t4 WHERE t2.two_nid = 1 OR t3.three_nid=1 OR t4.four_nid=1;
我要去哪裏錯了我的SQL查詢?
在此先感謝,如果需要更多信息,請不要猶豫。
乾杯隊友,工作。 –