About functions

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About functions

A function is a predefined, named formula that performs a specific calculation and returns a single, specific value.

Most functions include three basic parts:

the function

a set of parentheses, if the function takes parameters

the parameters required by the function

Each function returns a result of field type text, number, date, time, timestamp, or container.

Parameters

Function parameters can be constants (such as 1.07 or "hello"), field references (such as InvoiceTotal), expressions (such as 1 + 12), or other functions (such as the NPV function). You can use spaces before or after the parentheses used to enclose the parameters, but spaces are not necessary. When a function requires more than one parameter, separate individual parameters with a list separator, such as a semicolon.

Important See Design functions for information about literal text parameters.

Curly braces ({ }) surround optional parameters (for example, the Case function and Choose function). An ellipsis (...) signifies that you can add more parameters, each separated by a semicolon (for example, in aggregate functions). Double quotation marks(" ") indicate a text string.

This table shows examples of some FileMaker Pro functions.

This function

Returns

Length("John")

4, the number of characters in the text "John"

Round(SalesTax,2)

The amount of sales tax rounded to two decimal places

Position(Name, "Mc",1,1)

A number representing the starting position of one text string within another, in this case indicating the position of the first occurrence of "Mc" in the Name field

Get( LastError )

A number representing the error (if any) in the most recently executed script step in the currently running script (see Solving calculations on a host machine for information about running scripts in client/server and peer-to-peer environments)

Sum(ExtendedPrice)

The total of all the values in the repeating field ExtendedPrice

See About formulas for information about where functions can be used.

Functions reference (category list)