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69 lines
1.7 KiB
Markdown
69 lines
1.7 KiB
Markdown
---
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sidebar_position: 51
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sidebar_label: view
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---
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## view {#view}
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Turns a subquery into a table. The function implements views (see [CREATE VIEW](https://clickhouse.com/docs/en/sql-reference/statements/create/view/#create-view)). The resulting table does not store data, but only stores the specified `SELECT` query. When reading from the table, ClickHouse executes the query and deletes all unnecessary columns from the result.
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**Syntax**
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``` sql
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view(subquery)
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```
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**Arguments**
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- `subquery` — `SELECT` query.
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**Returned value**
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- A table.
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**Example**
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Input table:
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``` text
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┌─id─┬─name─────┬─days─┐
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│ 1 │ January │ 31 │
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│ 2 │ February │ 29 │
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│ 3 │ March │ 31 │
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│ 4 │ April │ 30 │
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└────┴──────────┴──────┘
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```
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Query:
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``` sql
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SELECT * FROM view(SELECT name FROM months);
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```
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Result:
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``` text
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┌─name─────┐
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│ January │
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│ February │
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│ March │
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│ April │
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└──────────┘
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```
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You can use the `view` function as a parameter of the [remote](https://clickhouse.com/docs/en/sql-reference/table-functions/remote/#remote-remotesecure) and [cluster](https://clickhouse.com/docs/en/sql-reference/table-functions/cluster/#cluster-clusterallreplicas) table functions:
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``` sql
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SELECT * FROM remote(`127.0.0.1`, view(SELECT a, b, c FROM table_name));
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```
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``` sql
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SELECT * FROM cluster(`cluster_name`, view(SELECT a, b, c FROM table_name));
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```
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**See Also**
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- [View Table Engine](https://clickhouse.com/docs/en/engines/table-engines/special/view/)
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[Original article](https://clickhouse.com/docs/en/sql-reference/table-functions/view/) <!--hide-->
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