If your file is a text file then you would use a Text Schema option under the Schema service.
Refer to the image below:
- If the header is present then check the 'Header Present' box
- If the record delimiter are in a new line (carriage return) then enter \n
- If the field delimiter is a tab then enter \t (or enter any other delimiter such as , | ~ etc depending on what the separator is in the file)
- If you have a data file in order to create the schema then select Data in the 'Use Definition File' option and click on Upload File button. A pop-up window will come up, click on Browse, upload your file and then click on Upload button and click Finish.
- Automatically all the Header columns will be read and these field names will be displayed in the panel.
- Click Save
Now once the schema is created you can go to Data Transform > create a new Map and load this schema (as source or target) and apply mapping rules.