| Student: | Book: | |||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| 2 | yong | null | def | |
| [Inner] Join | ||||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| Left [Outer] Join: 左表所有行， 右表没有匹配行则均为null | ||||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| 2 | yong | null | null | |
| Right [Outer] Join | ||||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| null | null | null | def | |
| Full [Outer] Join | ||||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| 2 | yong | null | null | |
| null | null | null | def | |
| CROSS JOIN | ||||
| ID | Name | SID | Book | |
| 1 | feng | 1 | abc | |
| 1 | feng | null | def | |
| 2 | yong | 1 | abc | |
| 2 | yong | null | def | |
Thursday, September 11, 2008
[SQL] Join Tables
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