Troubleshooting Validation Errors (Concept)

Autodesk Expression Builder

 
Troubleshooting Validation Errors
Concept Procedure
 
 
 

When you save an expression, it is always checked to be sure it is valid. You can also check whether your expression is valid before you save it.

The validation checks the syntax of the expression, whether the properties you specified are present in the current data store, and whether the values for those properties are valid.

When possible, the validation operation displays a message describing the errors it finds. Often, you can click this error message to place the cursor at the problem spot so you can correct it.

Validation might fail for one of the following reasons:

  • A separator character is missing or invalid. For example, you may use a function with arguments that need to be separated by commas. Perhaps one of the commas is missing, or you entered a semicolon instead of a comma.
  • An operator or property is missing. This is common in expressions with multiple conditions. For example, the expression PARCEL_VALUE > 100000 AND <200000 is invalid. It should be PARCEL_VALUE > 100000 AND PARCEL_VALUE < 200000. Notice that in the second example, PARCEL_VALUE appears twice, while in the first example it appears only once.
  • A character or property is the wrong type. You may have used an operator that requires a numeric value and inserted a text character instead. You may have used a function that requires a hexadecimal value and supplied a numeral instead. You may have used a text property when a numeric one was required.
  • A required value is missing or “empty.” Perhaps you failed to insert a property value or a value for an argument.
  • The expression is missing a bracket, quotation mark, or parenthesis character. For example, there is an opening bracket that has no related closing bracket. This is common in complex expressions.

The validation process can help you avoid many errors, but it cannot guarantee that your expression will work the way you intend when it is applied. Validation does not execute the query against actual data, it only checks that the expression syntax is correct and that the properties and values are valid for the current data store.