Metadata is data describing the data structure.

You can extract metadata from your flat data file or create it by your own. We will show you, how to extract it from input file.

Right-click the first edge and select New metadata → Extract from flat file.

Figure 1.15. Extracting Metadata

A wizard for metadata extraction opens. Use Browse button to open dialog to specify a file.

Figure 1.16. Introductory Window of Metadata Editor

Select the input.dat file in data-in directory and click the OK button.

Figure 1.17. Selecting Data File

The Metadata Editor fills up:

Figure 1.18. Metadata Editor (Introductory Pane Filled)

Click Next to specify metadata fields.

Figure 1.19. Metadata Editor (Editing Pane)

As you can see, the wizard guessed that the records consisted of three fields and it also understood that the third field values were integer numbers.

You can replace the three default field names (Field1, Field2 and Field3) with more descriptive ones: FirstName, LastName and Salary.

To do that, click the Field1 item and enter the new field name.

Figure 1.20. Renaming a Field

Do the same with the other two field names. The result will look like this:

Figure 1.21. All Fields Have Been Renamed

Now click Finish. This way you have created metadata. The metadata has been assigned to the edge.

	Note
	You can extract metadata on edges and on input components.