Retrieving Computed Values
You can retrieve computed values by using arithmetic and string operators in the SELECT clause of the statement.
The following computational operators may be used:
addition subtraction multiplication division string concatenation
See the Mimer SQL Reference Manual for information regarding the type and precision of the result of an arithmetic expression.
List room prices with a 12% reduction:SELECT PRICE, PRICE*0.88 FROM ROOM_PRICES;
Labels and Computed Values
The computed column is unnamed by default in the result table. A label may be used to provide a name:
For example:SELECT PRICE, PRICE*0.88 AS SPECIAL_RATE FROM ROOM_PRICES;
A column may also be 'computed' as a constant value, which adds an extra column to the result table.
For example:SELECT PRICE, '12% reduction:', PRICE*0.88 AS SPECIAL_RATE FROM ROOM_PRICES;
You may also retrieve a value computed using the values in two or more columns, providing that the data types are compatible.
Retrieve hotel names prefixed with the word 'HOTEL' and cities:SELECT 'HOTEL ' || NAME, CITY FROM HOTEL;
Padding Concatenated Strings
For string concatenation, column values are padded with trailing blanks to the length of the column definition.
For example:SELECT NAME || 'HOTEL', CITY FROM HOTEL;
When retrieving computed values, parentheses can be used to force the operation priority.
Without parentheses, the normal precedence rules for arithmetic apply, i.e. multiplication and division are performed before addition and subtraction, and operators with the same precedence are evaluated from left to right.
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