我有两张桌子:
ID Name indicator_1 indicator_2
1 text 1 1
2 text 1 1
3 text 1 1
4 text 2 1
5 text 2 1
6 text 2 2
7 text 2 2
8 text 3 2
FieldName Value Description
indicator_1 1 good
indicator_1 2 medium
indicator_1 3 bad
indicator_2 1 yes
indicator_2 2 no
有没有办法加入这两张桌子并到达:
ID Name indicator_1 indicator_2
1 text good yes
2 text good yes
3 text good yes
4 text medium yes
5 text medium yes
6 text medium no
7 text medium no
8 text bad no
这只是一个样本,实际表格中有大约70个指标......非常感谢
答案 0 :(得分:4)
SELECT t1.ID, t1.Name, t2a.Description, t2b.Description
FROM Table1 t1
INNER JOIN Table2 t2a ON t2a.FieldName = 'indicator_1' AND t2a.Value = t1.indicator_1
INNER JOIN Table2 t2b ON t2b.FieldName = 'indicator_2' AND t2b.Value = t1.indicator_2
根据您的实际数据,您可能希望将“INNER”更改为“LEFT”,但INNER JOIN可能就在这里。