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docs/en/sql-reference/data-types/newjson.md
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@ -58,10 +58,10 @@ SELECT json FROM test;
└───────────────────────────────────┘
```
Using CAST from 'String':
Using CAST from `String`:
```sql
SELECT '{"a" : {"b" : 42},"c" : [1, 2, 3], "d" : "Hello, World!"}'::JSON as json;
SELECT '{"a" : {"b" : 42},"c" : [1, 2, 3], "d" : "Hello, World!"}'::JSON AS json;
```
```text
@ -70,7 +70,47 @@ SELECT '{"a" : {"b" : 42},"c" : [1, 2, 3], "d" : "Hello, World!"}'::JSON as json
└────────────────────────────────────────────────┘
```
CAST from `JSON`, named `Tuple`, `Map` and `Object('json')` to `JSON` type will be supported later.
Using CAST from `Tuple`:
```sql
SELECT (tuple(42 AS b) AS a, [1, 2, 3] AS c, 'Hello, World!' AS d)::JSON AS json;
```
```text
┌─json───────────────────────────────────────────┐
│ {"a":{"b":42},"c":[1,2,3],"d":"Hello, World!"} │
└────────────────────────────────────────────────┘
```
Using CAST from `Map`:
```sql
SELECT map('a', map('b', 42), 'c', [1,2,3], 'd', 'Hello, World!')::JSON AS json;
```
```text
┌─json───────────────────────────────────────────┐
│ {"a":{"b":42},"c":[1,2,3],"d":"Hello, World!"} │
└────────────────────────────────────────────────┘
```
Using CAST from deprecated `Object('json')`:
```sql
SELECT '{"a" : {"b" : 42},"c" : [1, 2, 3], "d" : "Hello, World!"}'::Object('json')::JSON AS json;
```
```text
┌─json───────────────────────────────────────────┐
│ {"a":{"b":42},"c":[1,2,3],"d":"Hello, World!"} │
└────────────────────────────────────────────────┘
```
:::note
CAST from `Tuple`/`Map`/`Object('json')` to `JSON` is implemented via serializing the column into `String` column containing JSON objects and deserializing it back to `JSON` type column.
:::
CAST between `JSON` types with different arguments will be supported later.
## Reading JSON paths as subcolumns