SQLSERVER JOIN STATEMENT CONCLUETION

table: a

field? : a1??????? a2??????? a3

?a???????? ?b???????? ?c????????
?d???????? ?d???????? ?d????????
?e???????? ?e???????? ?e????????

table :b

field : b1??????? b2??????? b3

?a???????? ?b???????? ?c????????
?f???????? ?f???????? ?f????????
?g???????? ?g???????? ?g????????

1,INNER JOIN

Example:

statement : select * from a inner join b on a.a1 = b.b1

results:

a1????? a2??????? a3?????? b1?????? b2???????? b3

a???????? ?b???????? ?c???????? ?a???????? ?b???????? ?c????????

2,LEFT JOIN = LEFT OUTER JOIN

Example:

statement : select * from a left join b on a.a1 = b.b1

results:

a1????? a2??????? a3?????? b1?????? b2???????? b3

a???????? ?b???????? ?c???????? ?a???????? ?b???????? ?c????????
d???????? ?d???????? ?d???????? ?NULL?NULL?NULL
e???????? ?e???????? ?e???????? ?NULL?NULL?NULL

3,RIHGT JOIN? = RIGHT OUTER JOIN

Example:

statement : select * from a right join b on a.a1 = b.b1

results:

a1????? a2??????? a3?????? b1?????? b2???????? b3

a???????? ?b???????? ?c???????? ?a???????? ?b???????? ?c????????
NULL?NULL?NULL?f???????? ?f???????? ?f????????
NULL?NULL?NULL?g???????? ?g???????? ?g????????

4,FULL JOIN? = FULL OUTER JOIN

Example:

statement : select * from a full? join b on a.a1 = b.b1

results:

a1????? a2??????? a3?????? b1?????? b2???????? b3

a???????? ?b???????? ?c???????? ?a???????? ?b???????? ?c???????? d???????? ?d???????? ?d???????? ?NULL?NULL?NULLe???????? ?e???????? ?e???????? ?NULL?NULL?NULLNULL?NULL?NULL?f???????? ?f???????? ?f???????? NULL?NULL?NULL?g???????? ?g???????? ?g????????

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