Bcs filters

. Filters need to be defined on the read list operations (aka finders, as named in the BDC metadata model). There is a specific dialog to configure a filter for the read list operation as you can see on this image. (Double-click on the read list operation and

You need to click on the ‘Add Filter Parameter’ button

Click on the ‘(Click to Add)’ link on the Properties panel to configure the picker. You’ll find the following dialog:

Give the filter a name on the New Filter text box

Select a filter field to be used. In this example I want to filter by ‘Artist Name’ so I select that field.

Define the type of filter to use. For a complete list of filter types and how they work please refer to this article. It’s worth mentioning two frequently used filters types: Comparison and wildcard. For this example, the artist name can have multiple words. (i.e. ‘Franz Kohl’), let’s see what happens when I use each filter type:

Comparison: If you use the ‘equal’ operator we’ll expect the user to type the full artist name to find items. Hence it will only filter if the user types ‘Franz Kohl’, but will not work with either just ‘Franz’ or with just ‘Kohl’

Wildcard: If you use the ‘wildcard’ type then the filter will be send to the external system with wildcards. In this case it will filter if the user types ‘Franz’ or ‘Kohl’ (we’ll return all the artists that have the string ‘Franz’ as part of the name or vice-versa).

Finally, identify what to do if the filter value is null. You need to select this option if you have an external list associated with this ECT. Otherwise you’ll see no items when browsing the list (because the filter value will be null).

e will be null).

You can add more filter parameters as needed and add a AND/OR behavior to it. For instance, we are interested to filter by last name and zone.

design experience: when integrating specifically with databases, our tools generate the necessary queries to enable the designed filters. If you are using other types of BCS data sources such as web services, WCF or .NET assemblies you need to make sure that your filters are part of their API, before you can model them in SPD.

Here is an example of how the picker dialog is going to look like when we select a ‘wildcard’ type of filter on the artist name and we searh

Once multiple filters are defined on the ECT, the external item picker algorithm to apply those filters is the following: it appends the resulting items of each filter of each read list operation of the ECT. So to be more efficient we recommend not having a high number of filters/finders on each ECT as this can potentially result in calling a high number of operations on the ECT.

In summary, the most important piece of information for this post is: Always define filters on your ECT, especially when you are going