In this post I will show you how to fix an error that appears in my thermal printer plugin that says: Error en el servidor: sql: no rows in result set.
This error says that there are no rows in the database, and you may be wondering what printing has to do with a database, so that is exactly what I will discuss in this post.
In this Python programming tutorial you will learn how to create a REST API using Flask, SQLite 3 (for data), and JSON for data communication.
In the end you will have an API that you can consume from any client that could be an Android application, a browser with JavaScript or even another server language.
I will show you how to create an API that communicates using JSON and saves the data in SQLite 3. The API will be created with Flask, and we will use the Python programming language to handle all the data.
In this article about programming in the Go language (also known as Golang) we will see how to create a REST API that communicates through JSON, saving and displaying data from a MySQL / MariaDB database.
In the end we will have a REST API with Go using the 4 methods: POST, PUT, DELETE and GET using the Mux router. We are also going to implement the 4 operations of a database: insert, update, delete and select.
I will leave the full open source code at the end of the post.
Although there are millions of tutorials about MySQL and PHP, I decided to make mine but in a very very simple way. Before you start, you must have a basic knowledge in MySQL.
Source code of PHP file connection
It is worth mentioning that we will not see good practices of databases, relationships, etc. We will use the tables as they are, without looking at normalization, or things like that.
Note: this tutorial uses PDO, but remember that we can also use mysqli functions. Personally I recommend PDO, because it is object oriented. However, I hope to write a tutorial about mysqli in the future.