Using the Expression Builder
The Expression Builder dialog helps you construct expressions for Derive Fields, Filter Rows, Data Quality Analyzer, Filter Existing Rows, and Join nodes. This dialog provides a list of available fields, operators, and functions you can use to build expressions.
To open the Expression Builder dialog, right-click the node and click Configure. In the displayed dialog, select the required field and click Edit.
The following fields are available in the dialog:
Search Functions...
Click to open the Insert Function dialog, enter a keyword in Search By Keyword field, and click Search to find the function. The Search Results panel provides the list of matching functions.
Click on the required function, and the description for the function is displayed in the right panel. To insert the selected function into the expression, you can either double-click the function or click OK.
Check Expression
Click to check the validity of the expression and report any existing error(s).
Help
Click to view the following in the list:
Aggregation Help
Views the documentation on aggregation functions when building an aggregation expression.
Expression Language Help
Views the documentation on expression language. The documentation is also available on the Expression Language page.
Dialog Help
Views this topic.
Element tree
The left panel provides the Field References, Operators, Functions, and Constants that can be used to insert into the expression. To insert an element, double-click the element and drag it to the expression or select the element and press the Enter or Space key.
Field References
Provides a list of input fields that can be referenced in the expression. The field icon indicates its data type.
Operators
Provides a list of operators supported by expression language. The operators are organized by category.
Functions
Provides a list of functions available to the expression language, and it is organized by category. To see the description of a function, move the pointer over it. After a function is inserted into the expression, you must replace its argument names with appropriate values.
Constants
Provides a list of common constant values used by certain functions. All valid date or time part, granularity values, and valid tz database names for time zones are listed. Note:
• GMT offsets are also valid for date and time functions, but are not listed.
• Common date or time and number formats are listed, but many other valid formats are not listed.
Filter options
You can filter the elements in the tree by prefix. Enter the first few characters of a field, operator, or function in the text box located above the element tree and only the matching elements are displayed. To return to the normal view, delete the contents in the text area. Aggregations – When you are building an aggregation expression, the list of aggregation functions supported by the expression language are provided.
Expression editor
The editor displaying the expression that is built. You can insert the elements from the element tree or type in the editor.
Error Panel
The panel that displays any errors in the expression that is checked.
Last modified date: 01/06/2023