JSON (JavaScript Object Notation) is a data format that is used for sending and receiving data from web applications. It is an easy-to-use and efficient way of exchanging information between server-side applications and clients. Postgresql has recently added native JSON support to its database. This makes it easier for developers to work with JSON instead of writing complicated SQL code. In this article, we will explore what JSON is, how Postgresql stores and works with JSON, and common use cases for Postgresql JSON.
What is Json?
JSON is a lightweight data-exchange format that is easy to use and read. It was originally created as an alternative to XML as a way of exchanging data between browsers and servers. JSON data formats consist of key-value pairs and are created using JavaScript syntax. JSON is often used as an alternative to XML to exchange data between web applications, because it is easier to read and write than XML.
JSON is also used to store data in databases, as it is a lightweight and efficient way to store data. Additionally, JSON is often used to transfer data between web services, as it is a language-independent format that can be easily read and understood by any programming language. JSON is also used to create APIs, as it is a simple and efficient way to transfer data between applications.
Advantages of Using Postgresql Json
Postgresql’s support for native JSON provides many advantages for developers when working with JSON data. It is much faster than traditional SQL code for performing various operations on JSON data, such as inserting, updating, and deleting data. Also, since Postgresql supports indexing for JSON, it allows for faster searching and retrieval of data from a JSON field. Additionally, Postgresql also supports various other functions for transforming and manipulating JSON data.
Postgresql also provides a number of security features for JSON data, such as encryption and access control. This ensures that only authorized users can access the data, and that the data is kept secure. Furthermore, Postgresql also provides a number of tools for managing and monitoring JSON data, such as the pgAdmin tool, which allows users to easily view and manage their JSON data.
How Does Postgresql Json Work?
Postgresql stores JSON data in a binary format called the JSONB data type. This allows the database to store JSON data more efficiently than other data types. Postgresql offers support for indexing and searching through JSONB data types, which is why it is beneficial to store JSON data in Postgresql. Postgresql also offers various functions and operators that allow developers to traverse and manipulate JSON data.
Postgresql also provides a set of functions that allow developers to query JSON data. These functions allow developers to extract specific values from JSON data, as well as to construct complex queries that can traverse multiple levels of JSON data. Additionally, Postgresql provides a set of operators that allow developers to compare JSON data with other data types, such as strings and numbers.
Json Syntax
JSON syntax consists of key-value pairs and follows the same structure as the JavaScript object literal. Each key should be enclosed in double quotes and must be unique within the object, and each value can be of any datatype including strings, objects, arrays, numbers, or even booleans. Additionally, JSON allows for nesting of objects and arrays to create more complex objects.
JSON is a lightweight data-interchange format that is easy to read and write. It is language independent and can be used across multiple programming languages. It is also self-describing, meaning that the data structure is embedded within the JSON string itself, making it easier to parse and interpret.
Working with Json Datatypes in Postgresql
Postgresql supports two different datatypes for storing JSON data – the JSON and JSONB datatypes. The JSON datatype stores the data in text form while the JSONB datatype stores the data in a binary format. Using the JSONB type offers better performance and efficiency when querying or manipulating data. Additionally, Postgresql also offers operators and functions specifically designed for working with JSON data.
When working with JSON data in Postgresql, it is important to understand the differences between the two datatypes. The JSON datatype is more suitable for storing data that is not expected to change often, while the JSONB datatype is better suited for data that is expected to be frequently updated. Additionally, the JSONB datatype offers more flexibility when it comes to querying and manipulating data.
Creating a Table with a Json Column
To create a table with a JSON column in Postgresql, use the following syntax:
CREATE TABLE table_name (
column1 datatype,
column2 datatype,
...
json_column jsonb
);
The above syntax will create a table with a JSONB column called json_column.
When creating a table with a JSON column, it is important to note that the data type of the column must be set to JSONB. This is because JSONB is a binary representation of JSON data, which allows for faster access and manipulation of the data. Additionally, JSONB supports indexing, which can improve query performance.
Inserting Data into a Table with a Json Column
To insert data into a table with a JSON column, use the following syntax:
INSERT INTO table_name (
column1,
column2,
...
json_column
) VALUES (value1, value2, ..., 'json_data')
The above syntax will insert the specified data into the JSON column.
It is important to note that the data must be in valid JSON format in order for the insertion to be successful. If the data is not in valid JSON format, the insertion will fail and an error will be returned.
Querying Data from a Table with a Json Column
To query data from a table with a JSON column, use the following syntax:
SELECT
The above syntax will return the value associated with the specified key in the JSON column.
It is important to note that the JSON column must be of type jsonb in order for the query to work. If the column is of type json, the query will not return the expected results.
Updating Data in a Table with a Json Column
To update data in a table with a JSON column, use the following syntax:
UPDATE table_name SET json_column = jsonb_set(json_column, text[] '$.key', 'new_value') WHERE condition;
The above syntax will update the specified value in the JSON column.
Deleting Data from a Table with a Json Column
To delete data from a table with a JSON column, use the following syntax:
UPDATE table_name SET json_column = jsonb_delete(json_column, text[] '$.key') WHERE condition;
The above syntax will delete the specified value from the JSON column.
Common Use Cases for Postgresql Json
JSON columns can be used to store complex information that would otherwise require multiple tables or complicated SQL queries. This could include geographical coordinates, customer information, product details and more. Additionally, Postgresql also provides support for indexing on JSON columns, making it easier to search and query specific pieces of information from a large dataset.
Conclusion
Postgresql’s native support for JSON makes dealing with complex datasets easier and more efficient. The ability to store data in binary format as well as index it makes this an attractive option for developers who are working with large amounts of dynamic information. In this article we explored what JSON is, how Postgresql stores and works withJSON data, and common use cases for Postgresql JSON.
by the Bito team. 
