Oracle - What is a JOIN?
Explain types of JOIN in oracle - Feb 07, 2010 at 14:20 PM
by Shuchi Gauri
What is a JOIN? Explain types of JOIN in oracle.
A JOIN is used to match/equate different
fields from 2 or more tables using primary/foreign keys. Output is
based on type of Join and what is to be queries i.e. common data
between 2 tables, unique data, total data, or mutually exclusive
SELECT p.last_name, t.deptName FROM person p,
dept t WHERE p.id = t.id;
Find name and department name of students who
have been allotted a department
SELECT * from Emp INNER JOIN Dept WHERE
Extracts data that meets the JOIN conditions
only. A JOIN is by default INNER unless OUTER keyword is specified
for an OUTER JOIN.
SELECT distinct * from Emp LEFT OUTER JOIN
Dept Where Emp.empid=Dept.empid
It includes non matching rows also unlike
SELECT a.name,b.name from emp a, emp b WHERE
Joining a Table to itself.
Oracle - What is a JOIN? Explain types of JOIN in oracle - April 10, 2009
at 11:00 AM
What is a JOIN? Explain types of JOIN in
A join is a query that extracts data from
two or more tables, views or snapshots.
Types of JOIN
This is represented by (=) sign.
This join retrieves information by using equality condition.
If sign other than =, then it is non-equi
Self join is a join type between a row of a table to
another row of the same table.
This type fetches the row that
matches the join condition and rows that don’t match the join
What is oracle Join?, What are the guidelines for joins?, What
are the types of Join?...........
Types of joins are: Equijoins, Non-equijoins, self join, outer
Object data type is created using object type in oracle. The
object data type can only be created using SQL data type such as
Number, Varchar 2, Date etc............
CHAR and NCHAR are
character data types which and have a fixed length........