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Brendan Clement
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This PR is part of the documentation revamp. Once the full set of PRs is merged, we’ll publish the combined site to staging for review before updating docs.lancedb.com. The curation, SQL and operations pages contain outdated claims and examples that do not reliably work as written. This corrects those pages against the reviewed SDK and local server evidence, including prepared statements, background jobs, cleanup and monitoring. Integration guides are grouped with their examples in #4533. Function and Secret-object documentation stays unpublished until its release. The two Function pages are listed in `.mintignore` and left out of the navigation, and the sections about them on other pages are MDX comments. Stacked on #4533. Each MDX file has one PR owner. Rebase onto main after #4533 is squash-merged. Local assembly, Mint validation and link checks pass, and the assembled site shows no Function or Secret-object content. A local release rehearsal that uncomments the drafts and restores the navigation also passes. Hold publication until this PR and lancedb/sophon#8688 are on `main`.
97 lines
3.7 KiB
Plaintext
97 lines
3.7 KiB
Plaintext
---
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title: "Materialized view"
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sidebarTitle: "Materialized View"
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description: "Create, open, list and drop a table whose contents are defined by a query."
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icon: table
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keywords: ["materialized view", "create_materialized_view", "catalog", "ddl"]
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availability:
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oss: available
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enterprise: available
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summary: >-
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Both offerings support materialized views. See [Enterprise compatibility](#deployment) for connection and server requirements.
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---
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A materialized view is a table whose contents are defined by a query over
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another table. The query is recorded in the view's schema, and a refresh
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brings its stored rows up to date with the source.
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The result is an ordinary table -- queryable, indexable, searchable, and present
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in `table_names()`. Nothing about reading it is special.
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This page covers creating and managing one. Keeping it current is
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[Refresh a materialized view](/feature-engineering/materialized-views).
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<Note>
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In SQL, see [`REFRESH MATERIALIZED VIEW`](/sql/dml/refresh#refresh-materialized-view) and [`SHOW MATERIALIZED VIEWS`](/sql/ddl/materialized-view#show).
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</Note>
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## Create a materialized view {#create}
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<CodeGroup>
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```python Python icon="python"
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view = db.create_materialized_view(
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"recent_docs",
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source="documents",
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select=["id", "title", "embedding"],
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where="created_at > TIMESTAMP '2026-01-01 00:00:00'",
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)
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```
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```typescript TypeScript icon="square-js"
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const view = await db.createMaterializedView("recent_docs", "documents", {
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select: ["id", "title", "embedding"],
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where: "created_at > TIMESTAMP '2026-01-01 00:00:00'",
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});
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```
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</CodeGroup>
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`source` names the table the view reads. With Python SDK 0.40.0, create that
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table with stable row IDs before creating the view. The
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[complete example](/feature-engineering/materialized-views#create-and-refresh)
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shows the setup. `select`, `where` and `limit` define the query.
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## Open, list and drop views {#manage}
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| | Python | TypeScript | SQL |
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| --- | --- | --- | --- |
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| create | `create_materialized_view` | `createMaterializedView` | `CREATE MATERIALIZED VIEW` |
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| open | `open_materialized_view` | `openMaterializedView` | -- |
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| list | `list_materialized_views` | `listMaterializedViews` | `SHOW MATERIALIZED VIEWS` |
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| refresh | `refresh` | `refresh` | `REFRESH MATERIALIZED VIEW` |
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| drop | `drop_table` | `dropTable` | `DROP TABLE` |
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<Note>
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On a local database, `list_materialized_views` reads table schemas to find
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views. On Enterprise, it asks the server for the view listing, as
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`SHOW MATERIALIZED VIEWS` does.
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</Note>
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A view is dropped with `drop_table`, because a materialized view **is** a table.
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That also means dropping one removes stored rows -- unlike dropping a
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[view](/management/view), which removes only a saved query.
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## Read the view and its definition {#working}
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`view.table` is the underlying table, for querying, indexing, or search.
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`view.definition` contains the query's select list, predicate and limit. Both are properties; on an async view, the definition is read with
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`await view.definition()`.
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## Enterprise compatibility {#deployment}
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Enterprise supports creating and refreshing materialized views on remote
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compute. Use the SDK version supported by your deployment, or the
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[SQL interface](/sql/ddl/materialized-view). See
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[Enterprise refreshes](/feature-engineering/materialized-views#availability)
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for compatibility considerations when upgrading an existing pipeline.
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## Related guides {#next}
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<CardGroup cols={2}>
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<Card title="Refresh a materialized view" icon="arrows-rotate" href="/feature-engineering/materialized-views">
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How a refresh works, and what it writes.
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</Card>
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<Card title="Views" icon="eye" href="/management/view">
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The non-materialized counterpart, defined in SQL.
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</Card>
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</CardGroup>
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