Left connection and right connection

xiaoxiao2021-03-06  16

SQL> SELECT * FROM A;

A

------------

1

2

3

4

SQL> SELECT * FROM B;

A b C

---------- --------------------

1 4 10

2 5 11

5 6 12

6 7 13

SQL> SELECT A.A, B.A, B.B, B.C

From A, B

WHERE A.A = B.A;

A a b c

---------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1 1 4 10

2 2 5 11

SQL> SELECT A.A, B.A, B.B, B.C

From A, B

WHERE A.A = B.A ( );

A a b c

---------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1 1 4 10

2 2 5 11

3

4

SQL> SELECT A.A, B.A, B.B, B.C

From A, B

WHERE A.A = B.A ( ) and B.C> 10;

A a b c

---------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

2 2 5 11

SQL> SELECT A.A, B.A, B.B, B.C

From A, B

WHERE A.A = B.A ( ) and B.C ( )> 10;

A a b c

---------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1

2 2 5 11

3

4

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