Creating expressions

An expression is a combination of functions, operators, and values. They are used to create calculations, filters, SQL-based tables, and to modify a column's expression.

The expression editor is used to work with expressions in Data Modules, Dashboards, and Explore. It can be invoked from a number of places within these components, as documented in the topic Using the expression editor.

The expression editor provides the following elements to create expressions:

Operators
Operators specify what happens to the values on either side of the operator. Operators are similar to functions in that they manipulate data items and return a result.
Summaries
Predefined functions that return either a single summary value for a group of related values or a different summary value for each instance of a group of related values.
Constants
Fixed values that you can use in an expression.
Constructs
This list contains constructs and templates that can be used to create an expression. Templates combine multiple functions into a group. For example, the search case template includes the case, when, else, and end functions.
Business Date/Time functions
Business functions for performing date and time calculations.
Period predicates
Time period functions that evaluate to either true or false.
Vendor Specific Functions
SQL functions that are specific to databases that Cognos Analytics supports.
Common Functions
Standard SQL functions.
Macro Functions
Functions that can be used within a macro. A macro is enclosed between the number signs (#) at the beginning and at the end. Everything between the number signs is treated as a macro expression, and is executed at run time. A macro can contain one or more macro functions.

All these elements are documented in the expression editor. For more information, see Expression editor documentation.