Joining information objects
Joining information objects is similar to joining tables in a database. As in a table join, you join information objects through a common field. For example, suppose one information object retrieves customer data, such as name, customer ID, address, phone, and credit limit. Another information object retrieves order data, such as order number, order date, ship date, status, and customer ID. Both information objects include a customer ID field, which you use to join the information objects.
You can retrieve data from any number of information objects as long as there is a relationship, identified by common fields, among the information objects. Figure 11-1 shows three information objects and the fields that join them. The Customer IO is joined to the Orders IO through the customerNumber field, and the Orders IO is joined to the OrderDetails IO through the orderNumber field.
Figure 11-1  
How to join information objects
This procedure assumes you have created a new report design and selected an information object when prompted.
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Under Available Data, choose Modify, as shown in Figure 11-2. This figure also shows an example of Available Data displaying the data fields in the first information object, Customers.
Figure 11-2  
Join displays the information object, Customers, under List of Information Objects, as shown in Figure 11-3.
Figure 11-3  
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On Select Information Object, browse through the folders to find and select an information object. Figure 11-4 shows an example of Select Information Object displaying the contents of a folder, which includes two information objects.
Figure 11-4  
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In Left, select one information object. Then, in Right, select the other information object. Figure 11-5 shows an example where CustomerData and OrderData are selected in the Left and Right fields, respectively.
Figure 11-5  
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Figure 11-6  
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Add Join Condition lists all the fields in the first and second information objects.
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In Condition, select a comparison operator. Typically, you use the default operator, equal to. Figure 11-7 shows an example of a completed join condition. The join condition joins the information objects on their respective customerNumber fields. This condition retrieves only those rows in which the customerNumber values match.
Figure 11-7  
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Figure 11-8  
You have finished joining two information objects.
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Available Data displays all the data fields from the joined information objects that you can insert in a table in your report design. In Figure 11-9, Available Data shows the data fields in three information objects, CustomerData, OrderData, and OrderDetailsData.
Figure 11-9  

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