Validation Expressions

The validation expression is associated with both map and structure elements. You specify the expression in the Validate expression tab. These expressions require a Boolean value. If the value is true, the element is consider valid. If false, a validation report is generated. The validation report is generic in that it only indicates the validation of the element failed and gives the location of the failure.

If you want to provide more details about a validation result, use one of the different validation report functions, which you can put at the root of the validation expression. For the list of available Functions in Talend Data Mapper, see Functions.