Working with PostgreSQL Function Return JSON

PostgreSQL provides two native operators -> and ->> to help you query JSON data. These operators allow you to access JSON object fields by text or key.

The operator -> returns a JSON object field by text, whereas the operator ->> returns a JSON object field by key. For instance, if you have a table called `orders` with a column named `info` that stores JSON data, you can query this data using the following SQL statement:

```sql

SELECT info -> 'name' FROM orders;

```

This will return the value of the `name` field in the `info` JSON object.

On the other hand, if you want to query a specific key in the JSON object, you can use the operator ->> as follows:

```sql

SELECT info ->> 'name' FROM orders;

```

Both operators are useful when working with JSON data in PostgreSQL. They provide an efficient way to extract specific values from JSON objects.

In addition to these operators, PostgreSQL returns a result set in the form of JSON. This allows you to easily query and manipulate JSON data.

To get started, let's create a new table for practicing with JSON data type. The following SQL statement creates a `orders` table with two columns: `id` and `info`. The `id` column is the primary key that identifies each order, while the `info` column stores the data in the form of JSON:

```sql

CREATE TABLE orders (

id SERIAL PRIMARY KEY,

info JSON

);

```

Now that we have created the table, let's insert some data into it. The following SQL statement inserts a new row into the `orders` table with JSON data:

```sql

INSERT INTO orders (info) VALUES ('{'name': 'John', 'age': 30}');

```

As you can see, PostgreSQL supports native JSON data type since version 9.2. It provides many functions and operators for manipulating JSON data.

In summary, this tutorial has demonstrated how to work with PostgreSQL JSON data type and some useful operators and functions for handling JSON data. With these tools, you can efficiently query and manipulate JSON data in your PostgreSQL database.

Postgresql function return json