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.
Is This Answer Correct ? | 4 Yes | 0 No |
Post New Answer View All Answers
how to show all tables with 'mysql'? : Sql dba
What is a call statement? Explain with an example.
What is sql not null constraint?
How do you delete data from a table?
Explain the steps needed to create the scheduled job?
What is an implicit commit?
what is difference between delete and truncate commands? : Sql dba
What are stuff and replace function?
What is on delete restrict?
Where are my tempfiles, I don't see them in v$datafile or dba_data_file?
What are joins in sql?
What are the benefits of triggers?
What is the primary key?
How do I run a pl sql program?
how to use myisamchk to check or repair myisam tables? : Sql dba