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Merge pull request #17467 from ClickHouse/filimonov-doc-jsonasstring

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Document JSONAsString
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docs/en/interfaces/formats.md
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@ -25,6 +25,7 @@ The supported formats are:
| [Vertical](#vertical) | ✗ | ✔ |
| [VerticalRaw](#verticalraw) | ✗ | ✔ |
| [JSON](#json) | ✗ | ✔ |
| [JSONAsString](#jsonasstring) | ✔ | ✗ |
| [JSONString](#jsonstring) | ✗ | ✔ |
| [JSONCompact](#jsoncompact) | ✗ | ✔ |
| [JSONCompactString](#jsoncompactstring) | ✗ | ✔ |
@ -507,6 +508,34 @@ Example:
}
```
## JSONAsString {#jsonasstring}
In this format, a single JSON object is interpreted as a single value. If input has several JSON objects (comma separated) they will be interpreted as a sepatate rows.
This format can only be parsed for table with a single field of type [String](../sql-reference/data-types/string.md). The remaining columns must be set to [DEFAULT](../sql-reference/statements/create/table.md#default) or [MATERIALIZED](../sql-reference/statements/create/table.md#materialized), or omitted. Once you collect whole JSON object to string you can use [JSON functions](../sql-reference/functions/json-functions.md) to process it.
**Example**
Query:
``` sql
DROP TABLE IF EXISTS json_as_string;
CREATE TABLE json_as_string (json String) ENGINE = Memory;
INSERT INTO json_as_string FORMAT JSONAsString {"foo":{"bar":{"x":"y"},"baz":1}},{},{"any json stucture":1}
SELECT * FROM json_as_string;
```
Result:
``` text
┌─json──────────────────────────────┐
│ {"foo":{"bar":{"x":"y"},"baz":1}} │
│ {} │
│ {"any json stucture":1} │
└───────────────────────────────────┘
```
## JSONCompact {#jsoncompact}
## JSONCompactString {#jsoncompactstring}