In Oracle, MINUS operator is used to return all rows in the first SELECT statement that are not returned by the second SELECT statement.

Each SELECT statement has a dataset and the MINUS operator returns all documents from the first dataset and then removes all documents from the second dataset.

For example

Syntax

SELECT expression1, expression2, ... expression_n  
FROM table1  
WHERE conditions  
MINUS  
SELECT expression1, expression2, ... expression_n  
FROM table2  
WHERE conditions;  

Parameters

1- expression1, expression2, ... expression_n: It specifies the columns that you want to retrieve.

2- table1, table2: it specifies the tables that you want to retrieve records from.

3- conditions: it specifies the conditions that must be fulfilled for the records to be selected.

Note: The expressions must be same in number for both the SELECT statement and have similar datatype.

Oracle MINUS Example

This example will return one field with the same datatype from two tables "suppliers" and "order_details".

SELECT supplier_id  
FROM suppliers  
MINUS  
SELECT supplier_id  
FROM order_details;  

Output