ClickHouse/docs/en/sql-reference/table-functions/format.md

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---
slug: /en/sql-reference/table-functions/format
sidebar_position: 56
sidebar_label: format
---
# format
Parses data from arguments according to specified input format. If structure argument is not specified, it's extracted from the data.
**Syntax**
``` sql
format(format_name, [structure], data)
```
**Parameters**
- `format_name` — The [format](../../interfaces/formats.md#formats) of the data.
- `structure` - Structure of the table. Optional. Format 'column1_name column1_type, column2_name column2_type, ...'.
- `data` — String literal or constant expression that returns a string containing data in specified format
**Returned value**
A table with data parsed from `data` argument according to specified format and specified or extracted structure.
**Examples**
Without `structure` argument:
**Query:**
``` sql
SELECT * FROM format(JSONEachRow,
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
```
**Result:**
```response
┌───b─┬─a─────┐
│ 111 │ Hello │
│ 123 │ World │
│ 112 │ Hello │
│ 124 │ World │
└─────┴───────┘
```
**Query:**
```sql
DESC format(JSONEachRow,
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
```
**Result:**
```response
┌─name─┬─type──────────────┬─default_type─┬─default_expression─┬─comment─┬─codec_expression─┬─ttl_expression─┐
│ b │ Nullable(Float64) │ │ │ │ │ │
│ a │ Nullable(String) │ │ │ │ │ │
└──────┴───────────────────┴──────────────┴────────────────────┴─────────┴──────────────────┴────────────────┘
```
With `structure` argument:
**Query:**
```sql
SELECT * FROM format(JSONEachRow, 'a String, b UInt32',
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
```
**Result:**
```response
┌─a─────┬───b─┐
│ Hello │ 111 │
│ World │ 123 │
│ Hello │ 112 │
│ World │ 124 │
└───────┴─────┘
```
**See Also**
- [Formats](../../interfaces/formats.md)