What are the different types of joins and explain them
briefly.

Answer Posted / rahul koshti

There are 2 main type of joins :
Equijoin : Join N number of tables for equality =.
Non-Equijoin : Join N number of tables for other than
equality such as <>,<,>,IN,BETWEEN etc.

Technically there are total 3 different types of joins:
Cross Join: When join condition is missing then all rows
from one table gets joined with all rows from other table..
Inner Join: If a row has a NULL value in any one of the
columna of join conditin then that row will not fetched.
Outer Join: Even if the NULL values are present in any
columns of join condition that record will get fetched.
There are again 3 types of outer joins: Left, Right, Full.
Self Join : A table is joined with self.

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