Types of joins?

Answer Posted / sangeetha meda

1. Self Join
Self join is a query in which a table is Joined to itself.

Self joins are used to compare the values in a column to
the other values in the same column in the same table.

2.Equi Join or Inner join
Equi join is a join in which the rows are retrieved the
equality of the relation ship between columns in the tables.

Select only those rows that have values in common in the
columns specified in the ON clause.

3.Non Equi Join or Outer Join

Left Outer Join:

Retrieves the matching records in both the table and non
matching records in the first or left table.

Right Outer Join

retrieves the matching records in both the table and non
matching records in the second or the right table.

Full Outer Join

Retrieves all the records (means matching and non matching
records in both the tables).

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