ClickHouse/docs/en/sql-reference/table-functions/url.md
2022-06-02 04:55:18 -06:00

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---
sidebar_position: 41
sidebar_label: url
---
# url
`url` function creates a table from the `URL` with given `format` and `structure`.
`url` function may be used in `SELECT` and `INSERT` queries on data in [URL](../../engines/table-engines/special/url.md) tables.
**Syntax**
``` sql
url(URL, format, structure)
```
**Parameters**
- `URL` — HTTP or HTTPS server address, which can accept `GET` or `POST` requests (for `SELECT` or `INSERT` queries correspondingly). Type: [String](../../sql-reference/data-types/string.md).
- `format` — [Format](../../interfaces/formats.md#formats) of the data. Type: [String](../../sql-reference/data-types/string.md).
- `structure` — Table structure in `'UserID UInt64, Name String'` format. Determines column names and types. Type: [String](../../sql-reference/data-types/string.md).
**Returned value**
A table with the specified format and structure and with data from the defined `URL`.
**Examples**
Getting the first 3 lines of a table that contains columns of `String` and [UInt32](../../sql-reference/data-types/int-uint.md) type from HTTP-server which answers in [CSV](../../interfaces/formats.md#csv) format.
``` sql
SELECT * FROM url('http://127.0.0.1:12345/', CSV, 'column1 String, column2 UInt32') LIMIT 3;
```
Inserting data from a `URL` into a table:
``` sql
CREATE TABLE test_table (column1 String, column2 UInt32) ENGINE=Memory;
INSERT INTO FUNCTION url('http://127.0.0.1:8123/?query=INSERT+INTO+test_table+FORMAT+CSV', 'CSV', 'column1 String, column2 UInt32') VALUES ('http interface', 42);
SELECT * FROM test_table;
```
## Globs in URL {globs-in-url}
Patterns in curly brackets `{ }` are used to generate a set of shards or to specify failover addresses. Supported pattern types and examples see in the description of the [remote](remote.md#globs-in-addresses) function.
Character `|` inside patterns is used to specify failover addresses. They are iterated in the same order as listed in the pattern. The number of generated addresses is limited by [glob_expansion_max_elements](../../operations/settings/settings.md#glob_expansion_max_elements) setting.