## Arithmetic Operations

You can use expressions that have arithmetic operations (such as + for additions and - for subtractions).

### Prerequisites

You require the demo data for the SQL Tutorial.

Start the query tool SQL Studio as database administrator MONA with password RED and log on to the demo database instance DEMODB.

### Arithmetic in the Results Table

You can use a data query both to determine data that already exists in a table and calculate values on the basis of this data.

SELECT hno, price*7 weekly_price, type
FROM hotel.room
WHERE type = 'single' AND hno <50

Displaying the weekly price for a single room; the display has been restricted to those hotels with a hotel number below 50

Result

HNO | WEEKLY_PRICE | TYPE
10 | 945 | Single
20 | 490 | Single
30 | 315 | Single
40 | 595 | Single

### Arithmetic in Search Conditions

In search conditions, you can also use expressions that have arithmetic operations.

SELECT hno, type, price
FROM hotel.room
WHERE price*7 < 500 AND type = 'single'

Displaying the hotels whose weekly price for a single room is below 500.00 euro

Result

HNO | TYPE | PRICE
20 | Single | 70
30 | Single | 45
100 | Single | 60
110 | Single | 70

SELECT hno, type, price
FROM hotel.room
WHERE (price*1.05)*7 < 500 AND type = 'single'

Displaying the hotels whose weekly price for a single room is below 500.00 euro, even after a price increase of 5 percent

Result

HNO | TYPE | PRICE
30 | Single | 45
100 | Single | 60

See also:

SQL Reference Manual, Expression (expression)

More examples for Data Query