json_object
1. JSON_OBJECT Function
=======json_object
1. JSON_OBJECT Function
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62beThe JSON_OBJECT function in H2 database is used to create a JSON object with the specified key-value pairs.
2. Syntax
The syntax for the JSON_OBJECT function in H2 database is as follows:
JSON_OBJECT(key1, value1, key2, value2, ...)
Arguments
key1, key2, ...
: The keys for the JSON object. These should be strings.value1, value2, ...
: The corresponding values associated with the keys. These can be any valid JSON values.
Return
- The JSON_OBJECT function returns a JSON object with the specified key-value pairs.
3. Notes
- The keys and values can be column names, constants, or expressions.
- If a key or value is
NULL
, it will be converted to the JSONnull
value in the resulting object. - The JSON_OBJECT function can be used to construct complex JSON objects by nesting multiple JSON_OBJECT functions or combining with other JSON functions.
- H2 database supports the JSON format, but it does not provide the full range of JSON functions and operators available in other databases such as PostgreSQL or MySQL.
4. Examples
Here are a few examples demonstrating the usage of the JSON_OBJECT function in H2 database:
Example 1 - Creating a simple JSON object:
SELECT JSON_OBJECT('name', 'John', 'age', 30) AS json_object;
Output:
json_object
-------------------------
{"name":"John","age":30}
Example 2 - Creating a JSON object with values from columns:
CREATE TABLE employees (
id INT PRIMARY KEY,
name VARCHAR(100),
department VARCHAR(100)
);
INSERT INTO employees VALUES (1, 'Alice', 'HR'), (2, 'Bob', 'Finance');
SELECT JSON_OBJECT('id', id, 'name', name, 'department', department) AS json_object
FROM employees;
Output:
json_object
----------------------------
{"id":1,"name":"Alice","department":"HR"}
{"id":2,"name":"Bob","department":"Finance"}
5. Related Functions
- json_array - Create a JSON array with specified values.
- JSON_VALUE - Extract a scalar value from a JSON object or array.
- JSON_ARRAYAGG - Aggregate values into a JSON array.