Update the schema in a collection
It is sometimes necessary to change the underlaying schema behind a Solr collection. Find out how to do it for collections configured through instance directories and configs.
If your collection was configured using an instance directory, you can download the
instance directory, edit
schema.xml, then re-upload it to ZooKeeper.
For instructions, see Generate Solr collection configuration using instance directories.
If your collection was configured using a config, you can update the schema using the Schema API. For information on using the Schema API, see Schema API in the Apache Solr Reference Guide.