Schema-on-Write databases define the schema of your data; i.e. fields, structure, and mappings of data at ingestion time but Schema-on-Read applies the schema at search time, meaning that if you run a query on a Schema-on-Write database type the search time decreases but the ingestion time increases because your data is already indexed mapped and the heavy work was done at ingestion time, however in the other hand Schema-on-Read would prioritize ingesting data to avoid data loss hence increasing your queries' search time.