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View

Create, describe, list, and drop saved queries with SQL.

Applies to: Embedded ❌, Enterprise ✅

A view stores a query, not rows. Reading it runs the query against current data, so a view is never stale, and never faster than the query it wraps. It is the counterpart to a materialized view, which stores rows and is brought up to date by a refresh; both are catalog objects defined by a query, differing only in when that query runs.

The SDK methods create_view, describe_view, list_views, and drop_view submit SQL through the connection's Flight endpoint. drop_view_async returns a job of type query whose single id is the SQL query UUID. Waiting confirms catalog removal; physical cleanup can continue afterward.

CREATE VIEW

CREATE VIEW "recent_matches" AS
SELECT t1.floats
FROM "documents" AS t1
INNER JOIN "categories" AS t2 ON t1.ints = t2.ints

The statement returns one row with UTF-8 name, query, and schema columns. query contains the stored query, including any declared column aliases, and schema contains its Arrow schema as JSON. The schema metadata keys lancedb::view::default_db and lancedb::view::default_namespace identify the defining database and namespace. The root namespace is public; nested namespace components are separated by $.

DESCRIBE VIEW "recent_matches" returns the same metadata shape. Anything the dialect supports can define one: joins, predicates, aggregates, window functions.

Reading one

A view is queried like a table:

SELECT * FROM "recent_matches" WHERE floats > 0.5

Predicates applied to the view compose with the query inside it rather than filtering its output afterwards, so a selective filter does not pay for rows the view would have produced and then discarded.

DROP VIEW

DROP VIEW "recent_matches"

Removes the saved query. Unlike dropping a table, no data is removed: there was none to begin with.

Listing

SHOW VIEWS
SHOW VIEWS IN "analytics" WHERE name > 'previous_view' LIMIT 100

SHOW VIEWS returns ascending name values. The name cursor is scoped to the selected namespace.

Object commands retain their small results in shared storage even when general query-result copying is disabled, so asynchronous polling can use any query node.

Views and tables share a namespace, and both are things you can query. The catalog distinguishes them:

view names	the views in the database
table names	the tables
relation names	everything queryable (both)

Use the relation listing when the question is "what can I select from," and the separate listings when the distinction matters: before dropping, for instance, since dropping a view removes only the saved query while dropping a table removes data.

Choosing between a view and a materialized view

	View	Materialized view
Stores	the query	the rows
Freshness	always current	as of the last refresh
Read cost	the full query, every read	a table scan
Write cost	none	a refresh

Reach for a view when the query is cheap, or when reading stale rows would be wrong. Reach for a materialized view when the query is expensive and the data changes less often than it is read.

The privileges are separate too: CREATE_VIEW and CREATE_MATERIALIZED_VIEW are distinct grants on a namespace, so the ability to create one does not imply the other. See Authorization.

What to read next

Materialized ViewThe stored-rows counterpart.ManagementWhere views fit among the other catalog objects.