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Join:
·
Joins are used to join two or more tables
to extract the data
·
Joins are used to retrieve the
relational based data from the tables
·
Joins mainly used to filter the
records from the multiple tables
·
Joins can be used to retrieve the
matching and non-matching data
·
There are different types of joins available
in the RDBMS like equi, non-equi, cartitian/cross join, left outer, right outer.
·
Joins are used to join the table columns
with specific values or other table columns.
·
Join allows duplicates
Union
·
Union is a set function
·
Union is used to combine 2 or more select
query result set outputs
·
Union removes the duplicate rows from
the result set
·
Number and names of columns should
match in all the select queries
·
Union operator cannot be used in create
view statement.
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