Schemas specify the format of data witin HCL Link maps and flows.

Schemas are used to define inputs and outputs in maps, and to define input and output terminals in flows.

Schemas can describe any kind of data. Native schemas that describe arbitrary delimited, or fixed format data can be created using the Schema designer. HCL Link also supports defining JSON data by use of JSON templates. JSON templates are defined as self-describing examples of JSON data, or schema specifications. XML data can be described by importing an XSD specificaiton.

HCL Link provides a number of schema importers that generate schemas that describe data files, such as CSV, Excel, PDF, or COBOL Copybooks.

Additionally, many adapters generate schemas that describe their input or output data. For example, the JDBC adapter can generate a schema that describes the columns of a database table.