Derivation expressions provide the ability to translate values or to retrieve information otherwise not accessible in an interface format in [IDIF]. Data from within the [{$applicationname}] database may need to be translated to match the requirements from a receiving third party system. Also, data within a source file may need to be translated to match the [{$applicationname}] specifications.


!!Derivation Expression Logic for Inbound Interfaces
Inbound interfaces provide the ability to load a source file into ePersonality; this is done by running [LMTD]. The [LMTD] allows you to apply derivation expressions to variables within the record that is being loaded.

The [LMTD] respects most of the same derivation expressions that are used with SQL Loader. One exception that the [LMTD] does not respect is the BYPASS function. Instead you should define a qualifier record, this can be done using an existing column within the table or by defining a foreign field. The derivation expression in this situation would contain an IF statement or a Case When clause and the constant field would contain the result (i.e. True or False). For more information on this please review the chapter on loading with interfaces.

[LMTD] can handle multiple fields being referenced in a derivation expression, however, for [LMTD] purposes the syntax is slightly different. The multiple fields must be specified in brackets with a colon prefacing the field name, for example: (:PLPL.TIME_CODE).
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!!Calling Functions in [IDIF] for Outbound Interfaces
Define Interface Formats (IDIF) is the screen used within the system to define export interface definitions for processing by the various interface programs. Many of these interface programs support the use of derivation expressions, but not all. As at June 1, 2008, the following interface programs have this support:
*[UEEF] - Employee / Assignment Interface
*[UPPHF] - Pay History Interface
*[UBEF] - Employee / Benefits Interface
*[UPGLF] - General Ledger File Interface
*[UPDIF] - Disbursement File Interface
*[UENH] - New Hire Interface
*[UPVEND] - AP (Vendors) Interface
*[UPDTB] - Deposits to Bank Interface
*[UPROEF] - Canadian Record of Employment file interface
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!!Derivation Expressions Calling Database Functions
[{InsertPage page = 'CALLABLE FUNCTION'}]