Get a clear idea of ​​external connections in Oracle 9i

Question

External connections seem a little confusing to me.

Can anyone get a clear idea of external connections ( right, left and full )?

Answer 1

Common question / answer: / questions / 4908 / how-do-i-decide-when-to-use-right-joinsleft-joins-or-inner-joins-or-how-to-determine-which-table-is- on-which-side / 41050 # 41050

Reading this original article on the Code Project will help you a lot: Visual presentation of SQL joins .

Answer 2

Joines .

Oracle Outer , (+), .

Answer 3

, @Pranay Rana. , . , A union B, A except B ( A minus B Oracle) ..

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Answer 4

As I always think of it:

LEFT JOIN - keeps all rows selected on the left  
RIGHT JOIN - keeps all rows selected on the right  
FULL JOIN - keeps all rows selected on both sides  

Easy to keep in mind without going to Wikipedia or drawing diagrams.

PS Death to Oracle + add syntax!