Schema Application

When using a custom schema to process data, an origin applies the schema differently depending on the data format of the data:

Delimited data

When processing delimited data with a custom schema, the origin applies the first field name and data type in the schema to the first field in the record, and so on. Since existing field names are ignored, this enables you to rename fields while defining their data types.

For example, say you define an ItemID Integer field as the first field in a custom schema. When processing data, the origin names the first field in each record ItemID, regardless of the original field name, and applies the Integer data type to the field.

JSON data

When processing JSON data with a custom schema, an origin locates fields in the data based on the field names defined in the schema, then applies the specified data types to those fields. The origin also reorders the fields based on the order specified in the schema.

For example, say you define an ItemID String field as the first field in a custom schema. When processing data, the origin locates the ItemID field, applies the String data type, and makes it the first field in the resulting record.

Note: The field names in the schema must match the field names in the data exactly. Field names are case sensitive.