ClickHouse/docs/en/sql-reference/table-functions/format.md
2023-01-11 10:08:11 -05:00

73 lines
1.9 KiB
Markdown

---
slug: /en/sql-reference/table-functions/format
sidebar_position: 56
sidebar_label: format
---
# format
Extracts table structure from data and parses it according to specified input format.
**Syntax**
``` sql
format(format_name, data)
```
**Parameters**
- `format_name` — The [format](../../interfaces/formats.md#formats) of the data.
- `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 specified format and extracted schema.
**Examples**
**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) │ │ │ │ │ │
└──────┴───────────────────┴──────────────┴────────────────────┴─────────┴──────────────────┴────────────────┘
```
**See Also**
- [Formats](../../interfaces/formats.md)