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ID NAME
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1 dave
2 bl
3 big bird
4 exc
9 æå®
SQL> select * from dave;
ID NAME
---------- ----------
8 å®åº
1 dave
2 bl
1 bl
2 dave
3 dba
4 sf-express
5 dmm
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SQL> select * from dave a left join bl b on a.id = b.id;
ID NAME ID NAME
--------- ---------- ---------- ----------
1 bl 1 dave
1 dave 1 dave
2 dave 2 bl
2 bl 2 bl
3 dba 3 big bird
4 sf-express 4 exc
5 dmm -- æ¤å¤B表为nullï¼å 为没æå¹é å°
8 å®åº -- æ¤å¤B表为nullï¼å 为没æå¹é å°
SQL> select * from dave a left outer join bl b on a.id = b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
1 bl 1 dave
1 dave 1 dave
2 dave 2 bl
2 bl 2 bl
3 dba 3 big bird
4 sf-express 4 exc
5 dmm
8 å®åº
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SQL> Select * from dave a,bl b where a.id=b.id(+); -- 注æï¼ ç¨ï¼+ï¼ å°±è¦ç¨å ³é®åwhere
ID NAME ID NAME
---------- ---------- ---------- ----------
1 bl 1 dave
1 dave 1 dave
2 dave 2 bl
2 bl 2 bl
3 dba 3 big bird
4 sf-express 4 exc
5 dmm
8 å®åº
2.2 å³å¤è¿æ¥ï¼right outer join/ right joinï¼
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示ä¾ï¼
SQL> select * from dave a right join bl b on a.id = b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
1 dave 1 dave
2 bl 2 bl
1 bl 1 dave
2 dave 2 bl
3 dba 3 big bird
4 sf-express 4 exc
9 æå® --æ¤å¤å·¦è¡¨ä¸è¶³ç¨Null å¡«å
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SQL> select * from dave a right outer join bl b on a.id = b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
1 dave 1 dave
2 bl 2 bl
1 bl 1 dave
2 dave 2 bl
3 dba 3 big bird
4 sf-express 4 exc
9 æå® --æ¤å¤å·¦è¡¨ä¸è¶³ç¨Null å¡«å
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SQL> Select * from dave a,bl b where a.id(+)=b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
1 dave 1 dave
2 bl 2 bl
1 bl 1 dave
2 dave 2 bl
3 dba 3 big bird
4 sf-express 4 exc
9 æå®
2.3 å ¨å¤è¿æ¥ï¼full outer join/ full joinï¼
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SQL> select * from dave a full join bl b on a.id = b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
8 å®åº
1 dave 1 dave
2 bl 2 bl
1 bl 1 dave
2 dave 2 bl
3 dba 3 big bird
4 sf-express 4 exc
5 dmm
9 æå®
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SQL> select * from dave a full outer join bl b on a.id = b.id;
ID NAME ID NAME
---------- ---------- ---------- ----------
8 å®åº
1 dave 1 dave
2 bl 2 bl
1 bl 1 dave
2 dave 2 bl
3 dba 3 big bird
4 sf-express 4 exc
5 dmm
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