Expressions

An expression can be as simple as a field name or as complex as a calculation involving functions, concatenations, and data type conversions. The main purpose of the Expression Builder is to make creating expressions easy by providing lists of valid options. Expression Builder is accessed from the query designer, report designer, graph designer, system rules ,and default values, and other areas where expressions are used.

Note: The caption for the Expression Builder form varies based on the specific area accessed from.

Throughout FH, where expressions are used, there are fields that display the expression.

 

  1. Press Expression Builder or to display the expression builder.

    To create an expression, you can type it directly into the expression box (not labeled), or you can select items to have FH insert them into the expression box for you.

  2. Select available functions.

    • String functions are character string functions.
    • Math functions return numeric values.
    • Logical functions are expressions that are evaluated and return a True or False answer.
    • Date functions return date- or time-related information.

    Information on advanced functions is available in Expression Builder Advanced Section.

  3. Select Show Fields From to select from available tables and views that are open.
  4. Select a table or view to update the Fields (not labeled) box.
  5. Paste a field into the Expression field by either double-clicking the field or selecting the field in the fields (not labeled) box and press Enter.

  6. Press Verify to validate the syntax of the expression in the expression box if the corresponding table is open.

    If the expression is valid, Expression is valid is displayed in the status bar. If it is not valid or if the corresponding table is not open, FH displays an error message.

    This option is not enabled for remote views.

    Note: If you include a user-defined function call in the expression, Verify indicates an error, but there will not necessarily be an error when the expression is evaluated at run time.

  7. Press OK to finish.

 

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