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Brendan Clement
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The existing docs have 254 findings from our shared Vale rules. Contributors would otherwise inherit these when editing the same lines. Clean up the prose across 80 pages: correct product names and a repeated word, simplify a few phrases, and replace dashes with punctuation that fits each sentence. The pinned Vale scan now reports zero findings, with no suppressions.
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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