I have a json object which has list of anycodings_mysql products under a bill. I want to write a anycodings_mysql mysql function for it which reads the data anycodings_mysql from the json and iterates over it one by anycodings_mysql one and inserts the same data to product and anycodings_mysql bill tables. Show
Here is my json object
Here I have a mysql function which reads the anycodings_mysql data from the JSON
Now with these lines
I get the inner products json and the id of anycodings_mysql the 0th product. But I want a way to iterate anycodings_mysql over the array of the products. 30 Answers 1 : of Loop through JSON object in mysql functionYou can use a WHILE loop in conjunction anycodings_json with JSON_LENGTH to achieve this:
You'll probably need to do more than anycodings_json simply 'SELECT product' though ;-) NOTE: MySQL JSON functions were added in anycodings_json 5.7.8 so you'll need to check your MySQL anycodings_json version first. 0 2022-09-19T20:38:24+00:00 2022-09-19T20:38:24+00:00Answer Link mRahman 3 Answers 2 : of Loop through JSON object in mysql functionExtension to this answer, and if you anycodings_json want to loop through the keys of json anycodings_json object, you can do this via this way
0 2022-09-19T20:38:24+00:00 2022-09-19T20:38:24+00:00Answer Link raja IntroductionMySQL version 5.7.8 introduces a JSON data type that allows you to access data in JSON documents. SQL databases tend to be rigid in design. By its nature, the structured query language enforces data type and size constraints. In comparison, NoSQL databases encourage flexibility in design. In these schema-less databases, there is no imposed structural restriction, only data to be saved. The JSON data type in MySQL grants you the strengths of both of these systems. It allows you to structure some parts of your database and leave others to be flexible. The first half of this article will design a database with JSON fields. It will step through using the built-in functions available to MySQL to create, read, update, and delete rows. The second half of this article will utilize the Eloquent ORM with Laravel to communicate with the database. You will build an admin panel that supports displaying products, adding new products, modifying existing products, and deleting products. PrerequisitesIf you would like to follow along with this article, you will need:
Note: Laravel now provides a tool called Sail to work with Docker that will configure an environment with MySQL, PHP, and Composer. This may be an alternative option if you are having difficulty setting up your local environment. This tutorial was verified with MySQL v8.0.23, PHP v7.3.24, Composer v2.0.9, and Laravel v8.26.1. Step 1 — Defining the SchemaFor the purposes of this tutorial, you will be building from a schema that defines the inventory of an online store that sells a variety of electronics. Traditionally, the Entity–attribute–value model (EAV) pattern would be used to allow customers to compare the features of products. However, with the JSON data type, this use case can be approached differently. The database will be named Create the
The Create the
Create the
Next, add some sample
Then, add some
Next, create a
This table definition specifies foreign key constraints for the The Here is an entity relationship diagram of the created database: This database design is not the best in terms of efficiency and accuracy. There are some common real-world use cases that are not accounted for. For example, there is no price column in the Step 2 — Creating Data in the JSON FieldNow, you are going to create products to add to the database using Here are some example televisions with data on screen size, resolution, ports, and speakers using stringified JSON objects:
This example declares five different television products. Alternatively,
you could use the built-in The Here are some example mobile phones using the
This example declares five different mobile phone products. It also utilized the If you specify a single key multiple times, only the first key/value pair will be retained. This is called normalizing the JSON in MySQL’s terms. Also, as part of normalization, the object keys are sorted and the extra white-space between key/value pairs is removed. Additionally, you could use the built-in Note: In previous versions of MySQL, you could use
For the purpose of this tutorial, you will use the
Here are some example cameras using the
This example declares five different camera products. Notice that only objects are passed to the In the case of the For example, here is a collection of JSON objects with the same
This will produce an array of values:
Now, at this point, you can verify your queries by using the
This query will produce 15 Now, you can create data in the JSON field. Step 3 — Reading the Data from the JSON FieldNow that you have some products in the database to work with, you can experiment with reading the data. For typical MySQL values that are not of type JSON, you would usually rely upon a When you wish to select rows using a JSON field, you should be familiar with
the concept of a path expression. Path expressions use a dollar sign symbol ( When used in combination with the Consider a scenario where you are interested in all of the televisions that have at least one USB and one HDMI port:
The first argument to the Once you have extracted the keys you are interested in, you can use the MySQL operators such as the greater than symbol ( This query will produce three results: These three televisions have at least one USB port and one HDMI port. The “Bravia” and “Proton” models do not meet these conditions. Alternatively, the Revise the previous query to use the
Now, you can read data from the JSON field. Step 4 — Updating Data in the JSON FieldYou can update data in JSON fields with the First, update JSON fields with
The Examine the updated mobile phone category with the following query:
“Qualcomm” is now present for all mobile phones: Now, update JSON fields with
“Qualcomm” is now replaced with “Qualcomm Snapdragon” for all mobile phones: Lastly, update JSON fields with
“red” color is now applied to all televisions: All of these functions seem identical but there is a difference in the way they behave. The The The Now, you can update data from the JSON field. Step 5 — Deleting Data from the JSON FieldYou can delete data in JSON fields with the
Using
The Alternatively, you can Using
This query will remove the “Desire” and “Passion” models of mobile phones. Working with a specific attribute requires the use of the Now, you can delete data from the JSON field. Step 6 — Creating the MigrationsNow, create a new Laravel project. Warning: This web application is for tutorial purposes only and should not be used in a production setting. Open your terminal window and run the following command:
Navigate to the newly created project directory:
Configure your Laravel application to use a MySQL database. You may need to modify your You are going to create three migrations for Make a
Modify the database/migrations/(...)create_brands.php
Make a
Modify the database/migrations/(...)create_categories.php
The
Modify the database/migrations/(...)create_products.php
Pay attention to the Note: This will only work for database engines that support the JSON data type. Engines, such as older versions of MySQL will not be able to carry out these migrations. Similar to creating other types of table fields using the appropriate data type named method, you have created a JSON column using the Step 7 — Creating the ModelsYou are going to create three models for Create a
Modify the app/Models/Brand.php
Create a
Modify the app/Models/Category.php
Create a
Modify the app/Models/Product.php
The Step 8 — Creating a ProductThe focus of the remainder of this tutorial will be on the camera product category. You will be building a view with a form that has fields that are specific for cameras. For brevity, the television and mobile phone product categories will not be covered - but would be very similar in design. Create the controller for the camera product category:
Modify the app/Http/Controller/CameraController.php
This completes the Create a view by making a resources/views/product/camera/new.blade.php
The Modify the routes in routes/web.php
Serve the application with the following command:
Then, visit Step 9 — Fetching ProductsThe Modify the app/Http/Controller/CameraController.php
This completes the Create a view by making a resources/views/product/camera/show.blade.php
Modify the routes in routes/web.php
Serve the application with the following command:
Then, visit a valid Step 10 — Editing a ProductBy using a combination of the techniques for You can create a form similar to the one in
Now, the form displays the existing values, making it easier for users to see what needs updating. First, the Step 11 — Searching Based on JSON AttributesYou can also query JSON columns using the Eloquent ORM. Consider a search page that allows users to search for cameras based upon attributes that they are interested in.
The retrieved records will now be available to the Step 12 — Deleting a ProductUsing a non-JSON column attribute, you can delete products by specifying a For example, in the case of an
For JSON columns, specify a
In this example, this code will remove all products that have a ConclusionIn this article, you designed a MySQL database with the JSON data type and connected to it with a Laravel web application. Whenever you need to save data as key/value pairs in a separate table or work with flexible attributes for an entity, you should consider using a JSON data type field instead as it can heavily contribute to compressing your database design. If you are interested in diving deeper, the MySQL documentation is a great resource to explore JSON concepts further. For more information on Laravel, you can consult our tech talk on Getting Started with Laravel. Can we store JSON array in MySQL?MySQL supports a native JSON data type defined by RFC 7159 that enables efficient access to data in JSON (JavaScript Object Notation) documents. The JSON data type provides these advantages over storing JSON-format strings in a string column: Automatic validation of JSON documents stored in JSON columns.
Is looping an array is possible in JSON?Looping Using JSON
JSON stands for JavaScript Object Notation. It's a light format for storing and transferring data from one place to another. So in looping, it is one of the most commonly used techniques for transporting data that is the array format or in attribute values.
Can we query JSON in MySQL?MySQL supports a native JSON data type that supports automatic validation and optimized storage and access of the JSON documents. Although JSON data should preferably be stored in a NoSQL database such as MongoDB, you may still encounter tables with JSON data from time to time.
What is drawback of JSON in MySQL?The drawback? If your JSON has multiple fields with the same key, only one of them, the last one, will be retained. The other drawback is that MySQL doesn't support indexing JSON columns, which means that searching through your JSON documents could result in a full table scan.
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