In Apache Solr's managed-schema.xml, it is an attribute that can be specified for field types and field definitions. The default is docValues="false", which means that column-oriented data is not stored for the field in order to speed up sorting and faceting. If you want to speed up sorting and faceting, setting docValues="true" may improve performance. However, this will increase the index size accordingly.
In Apache Solr 9.7.0, the latest schema version 1.7 is implemented, and most fields/field types that support docValues are enabled by default.
