Use fields, functions, and operators to create expressions in the Expression Editor.
If you assign the value
Formula
to a field, you must create a formula or an expression for the field to take data from. Use the Expression Editor to create expressions.
In the following image, fields
str
and
str2
have the value
Formula
:
The Expression Editor comes with powerful functions that can invoke operating system features. You must review the content passed into the functions before using them.
To open the Expression Editor, click
f(x)
next to a field wit h the value
Formula
.
The following image shows the
Expression Editor
dialog box:
The Expression Editor contains the following sections:
Section 1, the
Fields
section. A list of input, output, and temporary fields that you define appears here.
Section 2, the
Functions
section. A list of common XQuery functions appears here. Select a function to view its meaning.
Section 3, the
Operators
section. A list of operators that you can use to build an expression appears here.
Section 4, the
Expression
section. The Expression you build appears here. The conditions and operators that you use are case sensitive.
The expression in the image defines a temporary field,
Total Status
, as
Pass
if three tasks that run in parallel succeed.
Next, the taskflow uses
Total Status
in a Data Decision step. If the value of
Total Status
is
Pass
, the taskflow runs another Data Task. If the value of
Total Status
is
Fail
, the taskflow ends.
The following image shows the taskflow that uses
Total Status
:
Use the following options to create an expression:
To add a field, click the
Fields
tab, drill down to the field that you want to use, and click
Add
.
To add an operator, click an operator in the
Operators
section. You can also manually enter an operator. For example, manually enter the
If
operator.
To add a function, click the
Functions
tab, drill down to the function you want to use, and click
Add
.
To add a comment, enter the comment in the Expression section with the following syntax:
(:<comment>:)
.
For example, enter
(:This is a sample comment:)
.
Use comments to give descriptive information about the expression or to specify a URL to access business documentation about the expression.
The Expression Editor validates the expression as you enter it. You cannot save an expression that is not valid.