You can specify a field reference in BMC Remedy AR System filter qualifications in three ways:

field – Filters have the native ability to check both the current transaction and then the database values of fields against the conditions in the qualification. i.e., unless restricted using one of ‘TR.’ or ‘DB.’ as prefix. Filters check the transaction value of the field in the current transaction first and if that is NULL, then uses the database value.

The value of a field in the current transaction will be NULL if the value has not been modified after the last retrieval. This helps Action Request System to achieve the best performance while transferring data between client and server.

TR.field If field reference on a Filter is specified like this, the Database value of the field is ignored while evaluating the qualification, even if the value in current Transaction is NULL. As we know, the transaction value of the field remains NULL if the field value has not changed in the current transaction.

This option is often used by AR System Developers to make the Filter perform the actions ONLY IF the field value is modified in the current transaction.

DB.field – If the field name is prefixed with ‘DB.’ , the Filter evaluates only the value existing in the Database value while parsing the qualifications. Value in current transaction is ignored irrespective of it is NULL or not.

If you specify only the field without prefixes, the database value is ignored every time if there is a non-NULL value in the current transaction.

Some developers tend to think the usage of TR. or DB. is not recommended. I am not yet sure about the reason why it is not. However, if you use it without properly understanding the meaning of each field reference mechanism, you might end up spending some extra time in debugging it. Also remember that the prefixes TR. and DB. are limiting a Filter’s native capability to check both transaction and database value in sequence, which may not be desirable always.

Key Words: Remedy AR System Filter Qualifications, Writing Filter Qualifications in BMC Remedy Action Request System Filters, Using TR. and DB. in Filter Qualifications. Field Reference in AR System Filter Qualifications, Field Referencing in ARS, Remedy ARS filter qualifications.