Difference Between Oracle Join and Union


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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