Oracle Multi-table query inside connection, outer JOIN statement summary

Later, the statement is added to the build table.

Existing two tables, WESTEMP staff table, with (wtdempid,wtdempname,wtddeptid) column, westdept Department table, there (wtddeptid,wtddeptname,wtddeptaddress) Column. Where westemp.wtddeptid can be equal to Westdept.wtddeptid.

1. Cross-connect: (for producing Cartesian product) (two kinds of notation)

1.1 SELECT * FROM Westemp a crosses join Westdept b--Cross join, used to generate Cartesian product
1.2. Select * FROM westemp a,westdept b

2. Natural connection (automatic search for the elimination of Cartesian product conditions)

SELECT * FROM Westemp a natural join westdept b--Natural Connection
3. Inner connection (to eliminate Cartesian product by the specified conditions)

3.1 SELECT * from Westemp a inner join westdept B in a.wtddeptid=b.wtddeptid--inner connection,
3.2 SELECT * from Westemp a joins westdept B on a.wtddeptid=b.wtddeptid--internal connection,

3.3 Select * from westemp a,westdept b where a.wtddeptid=b.wtddeptid--inside connection,

4. Full-Outer connection

SELECT * FROM Westemp a full outer joins westdept B on a.wtddeptid=b.wtddeptid--all-out connections
5. Right outer connection

5.1 Select * FROM westemp a right outer joins westdept B on a.wtddeptid=b.wtddeptid--left outer connection

5.2 Select * from westemp a,westdept b where A.wtddeptid=b.wtddeptid (+)--right outer join

6. Left Outer connection

6.1select * from Westemp a ieft outer join westdept B on a.wtddeptid=b.wtddeptid--left outer connection

6.2select * from westemp a,westdept b where A.wtddeptid (+) =b.wtddeptid--left outer connection

Multi-table Connection definition

Http://www.cnblogs.com/westward/p/5148028.html

Oracle Multi-table query inside connection, outer JOIN statement summary