ClickHouse/docs/en/sql-reference/table-functions/index.md
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[docs] split aggregate function and system table references (#11742)
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---
toc_folder_title: Table Functions
toc_priority: 34
toc_title: Introduction
---
# Table Functions {#table-functions}
Table functions are methods for constructing tables.
You can use table functions in:
- [FROM](../../sql-reference/statements/select/from.md) clause of the `SELECT` query.
The method for creating a temporary table that is available only in the current query. The table is deleted when the query finishes.
- [CREATE TABLE AS \<table\_function()\>](../../sql-reference/statements/create.md#create-table-query) query.
It's one of the methods of creating a table.
!!! warning "Warning"
You cant use table functions if the [allow\_ddl](../../operations/settings/permissions-for-queries.md#settings_allow_ddl) setting is disabled.
| Function | Description |
|-----------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------|
| [file](../../sql-reference/table-functions/file.md) | Creates a [File](../../engines/table-engines/special/file.md)-engine table. |
| [merge](../../sql-reference/table-functions/merge.md) | Creates a [Merge](../../engines/table-engines/special/merge.md)-engine table. |
| [numbers](../../sql-reference/table-functions/numbers.md) | Creates a table with a single column filled with integer numbers. |
| [remote](../../sql-reference/table-functions/remote.md) | Allows you to access remote servers without creating a [Distributed](../../engines/table-engines/special/distributed.md)-engine table. |
| [url](../../sql-reference/table-functions/url.md) | Creates a [Url](../../engines/table-engines/special/url.md)-engine table. |
| [mysql](../../sql-reference/table-functions/mysql.md) | Creates a [MySQL](../../engines/table-engines/integrations/mysql.md)-engine table. |
| [jdbc](../../sql-reference/table-functions/jdbc.md) | Creates a [JDBC](../../engines/table-engines/integrations/jdbc.md)-engine table. |
| [odbc](../../sql-reference/table-functions/odbc.md) | Creates a [ODBC](../../engines/table-engines/integrations/odbc.md)-engine table. |
| [hdfs](../../sql-reference/table-functions/hdfs.md) | Creates a [HDFS](../../engines/table-engines/integrations/hdfs.md)-engine table. |
[Original article](https://clickhouse.tech/docs/en/query_language/table_functions/) <!--hide-->