How to Parse Json In Oracle?

To parse JSON in Oracle, you can use the JSON functions and operators provided by Oracle Database. These functions allow you to extract data from JSON structures, navigate through the JSON hierarchy, and manipulate JSON objects and arrays. Some of the key functions for parsing JSON in Oracle are JSON_VALUE, JSON_QUERY, JSON_EXISTS, JSON_ARRAY, and JSON_OBJECT. These functions provide a powerful set of tools for working with JSON data in Oracle Database. You can use these functions in SQL queries, PL/SQL code, or even in stored procedures to parse and process JSON data effectively.

How to query JSON data in Oracle?

To query JSON data in Oracle, you can use the JSON_query function or the dot notation.

Here is an example using JSON_query function:

SELECT JSON_query(json_column, '$.key1.key2') as result FROM table_name;

This query will retrieve the value of key2 nested inside key1 in the JSON column.

Alternatively, you can use the dot notation to access the JSON data:

SELECT json_column.key1.key2 as result FROM table_name;

This will achieve the same result as the JSON_query function.

You can also use the JSON_table function to extract JSON data into columns in the result set:

SELECT jt.* FROM table_name t, JSON_table(t.json_column, '$.key1' COLUMNS ( key2 VARCHAR2 PATH '$.key2', key3 NUMBER PATH '$.key3' )) jt;

This query will extract the values of key2 and key3 nested inside key1 as separate columns in the result set.

How to add new elements to a JSON object in Oracle?

To add new elements to a JSON object in Oracle, you can use the JSON_MERGE function. Here is an example of how to add a new element to a JSON object:

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DECLARE
    json_obj JSON_OBJECT_T := JSON_OBJECT_T.PARSE('{"name":"John", "age":30}');
BEGIN
    json_obj := json_obj.JSON_MERGE('{"city":"New York"}');
    DBMS_OUTPUT.PUT_LINE(json_obj.TO_STRING());
END;

In this example, we first create a JSON object json_obj with the initial elements "name":"John" and "age":30. We then use the JSON_MERGE function to add a new element "city":"New York" to the JSON object. Finally, we use the TO_STRING() method to convert the JSON object back to a string and print it out.

You can use similar logic to add new elements to a JSON object in Oracle. Just make sure to adjust the JSON object and new element values accordingly.

How to store JSON data in a table in Oracle?

To store JSON data in a table in Oracle, you can use the native JSON data type that was introduced in Oracle Database 12c Release 2 (12.2). Here's how you can do it:

1. Create a table with a column of type JSON data:

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CREATE TABLE json_data_table (
    id NUMBER PRIMARY KEY,
    json_data JSON
);

1. Insert JSON data into the table:

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INSERT INTO json_data_table (id, json_data)
VALUES (1, '{"name": "John Doe", "age": 30}');

1. Retrieve and query the JSON data:

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SELECT json_data.name, json_data.age
FROM json_data_table
WHERE id = 1;

You can also use JSON functions provided by Oracle to query and manipulate the JSON data stored in the table. Some of the JSON functions available in Oracle include JSON_VALUE, JSON_EXISTS, JSON_QUERY, JSON_ARRAYAGG, JSON_OBJECTAGG, and more.

Keep in mind that storing JSON data in a table in Oracle may require upgrading to a version that supports the JSON data type if you are using an older version of the database. Additionally, make sure to properly validate and sanitize the JSON data before storing it in the table to prevent any security vulnerabilities.

What are some alternative methods for parsing JSON in Oracle?

1. Using PL/JSON: PL/JSON is a JSON parser for Oracle PL/SQL that allows you to easily parse JSON strings and convert them into Oracle data types.
2. Using APEX_JSON: APEX_JSON is a package in Oracle Application Express that allows you to parse and generate JSON data in PL/SQL.
3. Using the JSON_TABLE function: The JSON_TABLE function in Oracle allows you to convert JSON data into relational data, similar to how you would use the XMLTABLE function to convert XML data into relational data.
4. Using Java stored procedures: You can write Java stored procedures in Oracle that use the built-in Java libraries for parsing JSON data.
5. Using external libraries: There are also third-party libraries available for parsing JSON data in Oracle, such as JSON-lib and json-simple. These libraries provide additional functionality and flexibility for working with JSON data in Oracle.