Configuring Data Synchronization by Filtering Parameters

Filtering by a client parameter determines synchronization behavior and affects caching of Enterprise Information System (EIS) information on Unwired Server when a mobile business object (MBO) is accessed by a device application.

In the mobile application diagram, select the mobile business object (MBO) for which you want to add filter settings.
Right-click the MBO and select Detailed Properties.
Select the Parameters tab and click More>>.
Select the Filter by checkbox for any parameters that you want to use for synchronization.
- If the default value is not supplied by the client, Unwired Server synchronizes based on the specified default value.
  If you are using a Web service, Optional is always set to True if the service is mapped to an element that has maxOccurs=0 in the WSDL.
- If you specify a personalization key, the client is not required to provide a value, but you must define a value for the key before successfully synchronizing the MBO.
During subsequent synchronization, the client may provide different values for the parameter, all of which affects EIS data refresh results that Unwired Server performs.

You develop an MBO named "salesOrder" and define a Filter by parameter named "region". The default value of "region" is "Eastern". After the MBO is deployed to Unwired Server, the implications of setting Filter by are:

Unwired Server's Cache (consolidated database or CDb) is partitioned for the MBO data based on the value of the Filter by parameter. In this example, the "region" parameter is passed to the database MBO:
```
select * from sales_order where region = ?
```
The results from the select query populate the salesOrder MBO, but the MBO data's cache (CDb) is also partitioned by the region value (Eastern). Meaning that when the MBO executes with region equal to "Eastern", the set of rows returned is compared against the previously cached results only from a previous execution of the query with region equal to "Eastern". None of the CDb rows containing salesOrder data for the region equal to "Southern" are considered in this differential calculation.

If you unselect Filter by, redeploy, and run this query against the MBO:

select * from sales_order where region = ?

The first query after redeployment with region equal to "Eastern" populates the cache with Eastern region sales orders.
If the second query runs with region equal to "Southern", it is determined that all rows in the CDb are different, resulting in the deletion of all Eastern rows and inserting all Southern rows, with the additional overhead required to perform the operation. In this scenario, clients synchronizing this MBO see all the different rows because the data was not filtered by a parameter.