About schemas

A schema defines the contents of at least one input that you intend to map or one output you intend to map.

A schema is the mechanism for defining each element of your data. Similar to a data dictionary, a schema contains a collection of type definitions.

Because data definitions are defined in a schema, you should be familiar with the specifications that define your data before attempting to create one.

A data file is a simple example. The file is made up of records and each record is made up of fields. In this case, there are three kinds of data objects: a file, a record, and a field.

In a file of records, think of the data in terms of the three data objects. For example, one type defines the entire file; another type defines the entire record contained in that file. Other types in the same schema define the data fields of the record.

A schema has three datatype classifications: group, category, and item. The root type is the base type from which all other types stem, representing the data objects of all types in the schema. "Root" is the default name, however, you can modify any type name.

Types within a schema are listed in alphabetical order by default. To change the order for new types, modify the root type properties.

Link supports large metadata. It supports more than 65,536 types and 65,536 components in a single schema. To reduce the number of types that maps that use large schemas must process, trim these schemas so that they contain only the required types.