Salesforce formulas derive their value from other fields, expressions, or values. They can be used in a number of contexts, including custom fields for auto-calculating values, criteria for data validation and workflow, and Visualforce pages.
Informational functions are a great help in processes, for example; checking for blank values or the prior value of the field.
Here are the informational Functions available to you whether you are using formula builders in an object or a process or if you are writing the formula in an apex script or visual force page.
| Informational Functions | |
| ISBLANK | Determines whether an expression has a value and returns TRUE if it does not. If it contains a value, this function returns FALSE. |
| BLANKVALUE | Determines whether an expression has a value and returns a substitute expression if it does not. If the expression has a value, returns the value of the expression. |
| PRIORVALUE | Returns the previous value of a field. |
| AND | Returns TRUE response if all values are true; returns a FALSE response if one or more values are false. |
| CASE | Checks a given expression against a series of values. If the expression is equal to a value, returns the corresponding result. If it is not equal to any values, it returns the else_result. |
| ISCHANGED | Compares the value of a field to the previous value and returns TRUE if the values are different. If the values are the same, this function returns FALSE. |
| ISNEW | Checks whether the formula is running during the creation of a new record and returns TRUE if it is. If an existing record is being updated, this function returns FALSE. |
| ISNUMBER | Determines whether a text value is a number and returns TRUE if it is. Otherwise, it returns FALSE. |
| IF | Determines whether expressions are true or false. Returns a given value if true and another if false. |
| NOT | Returns FALSE for TRUE and TRUE for FALSE. |
| OR | Determines whether expressions are true or false. Returns TRUE if any expression is true. Returns FALSE if all expressions are false. |
