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Jack Ye
52684d50b9
OSS docs now own the full usage content for features that only run against an Enterprise deployment, since the client interface itself lives here; Enterprise docs keep only the parts specific to its own behavior. Sophon's overlay for these five pages is dropped since the OSS versions are now the complete reference. SQL Reference is restructured to match an object-type SQL manual (DDL by object, then DML, then DQL, then Expressions) instead of the old flat, loosely-ordered page list, absorbing the SQL client-connection guide and FTS-via-SQL examples into it.
63 lines
2.0 KiB
Plaintext
63 lines
2.0 KiB
Plaintext
---
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title: "Materialized View"
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sidebarTitle: "Materialized View"
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description: "SHOW MATERIALIZED VIEWS — creation and refresh are SDK and REFRESH statements, not CREATE."
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icon: table
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keywords: ["materialized view", "show materialized views", "sql"]
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---
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<Badge color="red">Enterprise</Badge> [SQL runs on a deployment.](/sql)
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A materialized view stores a query's result as rows, kept current by a refresh
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-- the counterpart to a [view](/sql/ddl/view), which stores only the query.
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<Note>
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There is no `CREATE MATERIALIZED VIEW` statement. Creation is
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[`create_materialized_view`](/management/materialized-view#create) in the SDK,
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since it needs SDK-level source-table validation (stable row ids) that a bare
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SQL statement has nowhere to check. Once created, it is entirely a SQL object:
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queried like a table, refreshed with SQL, listed with SQL.
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</Note>
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## SHOW MATERIALIZED VIEWS {#show}
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```sql
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SHOW MATERIALIZED VIEWS
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```
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<Note>
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Cheaper than the SDK equivalent. `list_materialized_views` finds views by
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reading every table's schema, costing one open per table; this asks the server.
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</Note>
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## Refreshing one {#refresh}
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```sql
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REFRESH MATERIALIZED VIEW chunks
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```
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See [REFRESH](/sql/dml/refresh#refresh-materialized-view) for the full syntax,
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including `full = true` and what `CASCADE` does not yet do.
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## Dropping one {#drop}
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A materialized view **is** a table, so it is dropped with
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[`DROP TABLE`](/sql/ddl/table#drop) -- which is also why dropping one removes
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stored rows, unlike dropping a [view](/sql/ddl/view#drop).
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<Note>
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**Enterprise job type:** `mat_view_refresh` for the refresh; `drop_table` for
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dropping it, same as any table.
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</Note>
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## What to read next {#next}
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<CardGroup cols={2}>
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<Card title="Materialized View" icon="table" href="/management/materialized-view">
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Creating one from the SDK, and the stable-row-ids requirement.
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</Card>
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<Card title="Refresh a materialized view" icon="arrows-rotate" href="/feature-engineering/materialized-views">
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Incremental refreshes, and what they cost.
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</Card>
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</CardGroup>
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