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59 lines
2.5 KiB
Markdown
59 lines
2.5 KiB
Markdown
---
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slug: /en/sql-reference/table-functions/url
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sidebar_position: 41
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sidebar_label: url
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---
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# url
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`url` function creates a table from the `URL` with given `format` and `structure`.
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`url` function may be used in `SELECT` and `INSERT` queries on data in [URL](../../engines/table-engines/special/url.md) tables.
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**Syntax**
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``` sql
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url(URL [,format] [,structure] [,headers])
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```
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**Parameters**
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- `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).
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- `format` — [Format](../../interfaces/formats.md#formats) of the data. Type: [String](../../sql-reference/data-types/string.md).
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- `structure` — Table structure in `'UserID UInt64, Name String'` format. Determines column names and types. Type: [String](../../sql-reference/data-types/string.md).
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- `headers` - Headers in `'headers('key1'='value1', 'key2'='value2')'` format. You can set headers for HTTP call.
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**Returned value**
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A table with the specified format and structure and with data from the defined `URL`.
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**Examples**
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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.
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``` sql
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SELECT * FROM url('http://127.0.0.1:12345/', CSV, 'column1 String, column2 UInt32', headers('Accept'='text/csv; charset=utf-8')) LIMIT 3;
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```
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Inserting data from a `URL` into a table:
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``` sql
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CREATE TABLE test_table (column1 String, column2 UInt32) ENGINE=Memory;
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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);
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SELECT * FROM test_table;
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```
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## Globs in URL
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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.
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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.
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## Virtual Columns
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- `_path` — Path to the `URL`.
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- `_file` — Resource name of the `URL`.
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**See Also**
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- [Virtual columns](/docs/en/engines/table-engines/index.md#table_engines-virtual_columns)
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