![]() To practice with handling JSON data, let's create a simple table orders that has a info column storing the orders details. The use of JSON data gives more flexibility as we can add and remove attributes without changing our schema by adding and deleting columns. The JSONB data type takes more disk space but is preferable when doing a lot of operations on the JSON data or when indexing the JSON column. In PostgreSQL, JSON data is stored in plain text while JSONB data is stored in some binary representation. The values of phoneNumbers and children are arrays. The query stated below has given us the 10 pairs of key-value for 5 records of the table “Makeup” from the column “data”.The values or the firstName, isAlive and age keys are strings, boolean or numbers. The operator -> returns JSON object field by text. The operator -> returns JSON object field by key. The json_Each function takes the column “data” as a parameter within the SELECT query to fetch the key-value outermost pair. PostgreSQL provides two native operators -> and -> to help you query JSON data. The other values in the brackets will be the value of a key outside of the bracket, e.g., “details”. In the above-shown table, “Product” is an outermost key and the “Highlighter” is the outermost value of it. Our first JSON method will be the json_each() method to expand most outer objects of JSON into a pair of key-value. Let’s explore some JSON functions to fetch the key-value pairs of the respective column “data” of the table “Makeup”. The output will be as same as demonstrated in the picture below. It will expand further, and you have to tap the “All Rows” option to fetch the data in a grid view. Right-click on it and hover over the option of “View/Edit Data”. To see if the JSON type column and data have been created and inserted within the Postgres database successfully, you must see the Tables area. ![]() The queries worked perfectly fine, and the success message has been shown in the Output area. The “run” button on the taskbar of query editor has been pressed to execute this code, as shown below. Let’s say we have to query a user table with a metadata JSONB column on a PostgreSQL 9.5+ database. Another command, e.g., INSERT INT, has been used to insert the key-value pairs or JSON type information regarding makeup products into a column “data” of table Makeup. Knex.js (pronounced /knks/) is a batteries included SQL query builder for PostgreSQL, CockroachDB, MSSQL, MySQL, MariaDB, SQLite3, Better-SQLite3. How to query JSONB, beginner sheet cheat. Another is JSON type column “data” used to store the key-value pair information within this column of the Makeup table. One of them stores the ID of the makeup product, and the system automatically increments it. We have used the CREATE TABLE command to create a new table “Makeup” within the built-in database Postgres. Now the query tool has been opened, you have to add some code to it to create JSON data. After adding the password, you have to tap on any database listed within the list of Servers and open the query tool to add some commands. After that, it may require your master password and server password to get into it one after another. Open your PostgreSQL Graphical user interface, e.g., pgAdmin, from the start bar of Windows 10 by searching it thoroughly. ![]() Make sure you have PostgreSQL pgAmdin 4 installed and configured on your Windows 10 system because we have been implementing this article at Windows 10 on the PostgreSQL pgAdmin 4. To work on JSON functions, one must have some JSON data in the database. In this article, we will demonstrate the working of JSON functions on some JSON data within the PostgreSQL tool. JSON consists of many operators and functions to query the JSON information or data. JSON is an open-style JavaScript Object Notation used only for pairs of key-value data within the PostgreSQL database.
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