text: of this exercise, we will create a collection called langchain_demo. Since Rockset supports schemaless ingest, you don't need to inform us of the shape of metadata for your texts. However, you do need to decide on two columns upfront:Where to store the text. We will use the column description for this.Where to store the vector-embedding for the text. We will use the column description_embedding for this.Also you will need to inform Rockset that description_embedding is a vector-embedding, so that we can optimize its format. You can do this using a Rockset ingest transformation while creating your collection:SELECT