A common problem customers have is extracting data from repeating segments in messages. Consider the following message:

MSH|^~\&||.|||199908180016||ADT^A04|ADT.1.1698593|P|2.5
PID|1||000395122||LEVERKUHN^ADRIAN^C^^^||19880517180606|M|^^^^^||6 66TH AVE NE^^WEIMAR^DL^98052||(157)983-3296|||S||12354768|87654321
NK1|1|TALLIS^THOMAS^C|GRANDFATHER|12914 SPEM ST^^ALIUM^IN^98052|(157)883-6176
NK1|2|WEBERN^ANTON|SON|12 STRASSE MUSIK^^VIENNA^AUS^11212|(123)456-7890
PV1|1|E|EMG-W^^|1||||||||||ER||||ER||H|||||||||||||||||||OVL||REG|||199908180015
GT1|1||SMITH^JAMES^M||12914 164TH AVE NE^^RICHMOND^ON^98052|(157)883-6176|||||F|535-52-9776||||WEISS JENSON|.^^WELLINGTON^ON^.|(206)340-9577 
IN1|1|PRE2||LIFE PRUDENT BUYER|PO BOX 23523^WELLINGTON^ON^98111|||19601||||||||THOMAS^JAMES^M|F|||||||||||||||||||ZKA535529776>

The above message contains the following segments:

• MSH
• PID
• NK1[1]
• NK1[2] (repeating segment)
• PV1
• GT1
• IN1

Since the NK1 segment occurs more than once, you obviously want to keep the data from both segments instead of just overwriting the data. This can easily be done using Chameleon.

To properly extract data from repeating segments:

• Double-click Message Grammar in the Workspace. The Message Grammar window appears.
• Add the repeating segment to the Segment Grammar (in this case, NK1).
• In the Segment Grammar panel, ensure that Repeating is checked. Setting this field to 0 means that this segment may repeat an unlimited number of times.

Adding the Repeating NK1 Segment to the Segment Grammar

• Create a new table for the segment that may repeat (e.g. Next of Kin).
• Define the new table as desired. For example, you might want to extract the following data: First Name, Surname, Relationship to Patient and Phone Number.

Defining the Next of Kin Table

• Drag-and-drop the newly created table into the Table Grammar panel.
• Double-click the Next_of_Kin table. A dialog window appears, informing you that you first have to define the grammar root.
• Click OK to define the grammar root. The Grammar Selection window appears.

Selecting the Grammar Root

• Select {NK1} (Next of Kin/Associated Parties} as the Grammar Root, and click OK. The Grammar Root must be the segment that will repeat.

	When you select NK1 as the grammar root, only fields for NK1 are available. This means you cannot access data from other segments, which will help you correctly map the data.

• In the Table Mapping window, specify the segment fields to associate with the data elements you want to extract. You can do this by dragging and dropping fields from the right pane to the Mapping column as shown below. When you parse a message, correct mappings will ensure that your message is parsed properly.

Table Mapping Window

• Click the Message Browser button on the toolbar, and paste the sample message from the top of the page.
• Click the Parse button, followed by the Table View tab.
• Click the Text View option. The mappings for all of your tables in your table grammar will be displayed.

Message Browser, Showing Text View

Notice that the Next_of_Kin table has been filled with two rows of data, one for each NK1 segment in the message.