A classifier model contains reference data rows and label values. The rows represent the input data on the port that you might connect to the Classifier transformation. The label values describe the types of information that the data rows contain. When you configure a classifier model, you assign a label to each reference data row in the model.

To link the reference data rows to the labels in a classifier model, you compile the model. The compilation process generates a series of logical associations between the data rows and the label values. When you run a mapping that reads the model, the Data Integration Service applies the model logic to the Classifier transformation input data. The Data Integration Service returns the labels that most accurately describe the information in each input data field.

You create a classifier model in the Developer tool. The Model repository stores the classifier model object. The Developer tool writes the data rows, the labels, and the compilation data to a file in the Informatica directory structure.