diff --git a/docs/virtual_db.md b/docs/virtual_db.md
index e3b40ac..3ec4b45 100644
--- a/docs/virtual_db.md
+++ b/docs/virtual_db.md
@@ -1,27 +1,31 @@
 # VirtualDB
 
-VirtualDB provides a unified query interface across heterogeneous datasets with
-different experimental condition structures and terminologies. Each dataset
-defines experimental conditions in its own way, with properties stored at
-different hierarchy levels (repository, dataset, or field) and using different
-naming conventions. VirtualDB uses an external YAML configuration to map these
-varying structures to a common schema, normalize factor level names (e.g.,
-"D-glucose", "dextrose", "glu" all become "glucose"), and enable cross-dataset
-queries with standardized field names and values.
+VirtualDB provides a SQL query interface across heterogeneous HuggingFace
+datasets using an in-memory DuckDB database. Each dataset defines experimental
+conditions in its own way, with properties stored at different hierarchy levels
+(repository, dataset, or field) and using different naming conventions.
+VirtualDB uses an external YAML configuration to map these varying structures
+to a common schema, normalize factor level names (e.g., "D-glucose",
+"dextrose", "glu" all become "glucose"), and enable cross-dataset queries with
+standardized field names and values.
 
-## API Reference
+For primary datasets, VirtualDB creates:
 
-::: tfbpapi.virtual_db.VirtualDB
-    options:
-      show_root_heading: true
-      show_source: true
+- **`<db_name>_meta`** -- one row per sample with derived metadata columns
+- **`<db_name>`** -- full measurement-level data joined to the metadata view
 
-### Helper Functions
+For comparative analysis datasets, VirtualDB creates:
 
-::: tfbpapi.virtual_db.get_nested_value
-    options:
-      show_root_heading: true
+- **`<db_name>_expanded`** -- the raw data with composite ID fields parsed
+  into `<link_field>_source` (aliased to configured `db_name`) and
+  `<link_field>_id` (sample_id) columns
+
+See the [configuration guide](virtual_db_configuration.md) for setup details
+and the [tutorial](tutorials/virtual_db_tutorial.ipynb) for usage examples.
+
+## API Reference
 
-::: tfbpapi.virtual_db.normalize_value
+::: tfbpapi.virtual_db.VirtualDB
     options:
       show_root_heading: true
+      show_source: true
diff --git a/tfbpapi/virtual_db.py b/tfbpapi/virtual_db.py
index 4fd6f3c..96097a3 100644
--- a/tfbpapi/virtual_db.py
+++ b/tfbpapi/virtual_db.py
@@ -6,13 +6,14 @@
 https://brentlab.github.io/tfbpapi/huggingface_datacard/. Next, a developer can create
 a virtualDB configuration file that describes which huggingface repos and datasets to
 use, a set of common fields, datasets that contain comparative analytics, and more.
-VirtualDB, this code, then uses DuckDB to construct tables and views are
-which are lazily created over Parquet files which are cached locally. VirtualDB uses
-the information in the datacard to create metadata views which describe sample level
-features. Derived columns are attached to both the metadata and full data views. Any
-comparative analysis datasets are also parsed and joined to the primary datasets'
-metadata views. The expectation is that a developer will use this interface to write
-SQL queries against the views to provide an API to downstream users and applications.
+VirtualDB, this code, then uses DuckDB to construct views that are lazily created
+over Parquet files cached locally. For primary datasets, VirtualDB creates metadata
+views (one row per sample with derived columns) and full data views (measurement-level
+data joined to metadata). For comparative analysis datasets, VirtualDB creates expanded
+views that parse composite ID fields into ``_source`` (aliased to the configured
+db_name) and ``_id`` (sample_id) columns. The expectation is that a developer will
+use this interface to write SQL queries against the views to provide an API to
+downstream users and applications.
 
 Example Usage::