SQL Reference

Expressions

An expression specifies a value. It can be a simple value, consisting of only a constant or a column name, or it can be more complex. When repeatedly using similar complex expressions, the usage of an SQL function may be considered to encapsulate a common expression. See CREATE FUNCTION (SQL Scalar, Table or Row) for more information.

   .-operator-----------------------------------.
   V                                            |
>>----+-----+---+-function-------------------+--+--------------><
      +- + -+   +-(expression)---------------+
      '- - -'   +-constant-------------------+
                +-column-name----------------+
                +-host-variable--------------+
                +-special-register-----------+
                |                     (1)    |
                +-(scalar-fullselect)--------+
                |                  (2)       |
                +-labeled-duration-----------+
                |                 (3)        |
                +-case-expression------------+
                |                    (4)     |
                +-cast-specification---------+
                |                       (5)  |
                +-dereference-operation------+
                |               (6)          |
                +-OLAP-function--------------+
                |                   (7)      |
                +-method-invocation----------+
                |                   (8)      |
                '-subtype-treatment----------'
 
operator
 
             (9)
|---+-CONCAT------+---------------------------------------------|
    +- / ---------+
    +- * ---------+
    +- + ---------+
    '- - ---------'
 

Notes:

1. See Scalar Fullselect for more information.

2. See Labeled Durations for more information.

3. See CASE Expressions for more information.

4. See CAST Specifications for more information.

5. See Dereference Operations for more information.

6. See OLAP Functions for more information.

7. See Method Invocation for more information.

8. See Subtype Treatment for more information.

9. || may be used as a synonym for CONCAT.

Without Operators

If no operators are used, the result of the expression is the specified value.

Examples: SALARY :SALARY 'SALARY' MAX(SALARY)