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Visualization of the trade information of agricultural products
Published in Xiaoling Jia, Feng Wu, Electromechanical Control Technology and Transportation, 2017
According to the requirement analysis, the key of the system is to access data from database. In this page, ORM (Object Relation Mapping) is used to access the database (Paul K Harmer, 2002). ORM, a programming technique, is used to achieve the transformation of the data between different types of systems in an object-oriented programming language. The flask framework implements the ORM mechanism through a third-party library named flask_sqlachemy. The specific code is as follows:
Web Application Frameworks
Published in Akshi Kumar, Web Technology, 2018
Django’s offers a complete and versatile solution that can be used to to build almost any type of web site (from wikis to social networks), making it a prominent choice for powering web sites. Major sites like Pinterest (a pinboard-style photo sharing site), Bitbucket (a code sharing site), and Instagram (a photo sharing site) are few examples of web sites powered by Django. A few characteristics that make it a popular choice to code web sites are: It has Object-Relational Mapping (ORM) support: ORM is a technique that enables querying and manipulating data from a database using an object-oriented paradigm. An object-relational mapper is a code library that automates the transfer of data stored in relational database tables into objects that are more commonly used in application code. Django provides a bridge between the data model and the database engine and supports a large set of database systems including MySQL and NoSQL databases. ORMs provide a high-level abstraction upon a relational database that allows a developer to write Python code instead of SQL to create, read, update, and delete data and schemas in a database.It has multilingual support: Django supports multilingual web sites through its built-in internationalization system.It is a Development Environment: Django comes with a lightweight web server to facilitate end-to-end application development and testing.It has Framework Support: Django has built-in support for AJAX, RSS, caching, and other frameworks.It is portable: Django is written in Python, which runs on many platforms.It is maintainable: Django code is written using design principles and patterns that encourage the creation of maintainable and reusable code. In particular, it makes use of the “don’t repeat yourself” (DRY) principle to avoid unnecessary duplication.
Air quality monitoring platform with multiple data source support
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Dessislava Petrova-Antonova, Jelyazko Jelyazkov, Irena Pavlova
The architecture of the platform consists of 5 layers as follows: Data storage layer – stores data in SQLite database. Since the SQLite does not require separate server process and related configuration, it is used as an embedded SQL database engine. Thus, minimal requirements to the deployment environment are achieved.Object Relational Mapping (ORM) layer – provides a level of abstraction between the database and the business layer. Thus, the database could be easily replaced. The mapping is implemented by a Hibernate ORP provider.Business layer – processes data collected from the external APIs and provides data to the services called by the client’s interface.Interface layer – implements services for communication with the external APIs and client’s interface.External APIs layer – delivers data from different sources, which the platform aggregates.Client’s interface layer – implements the user interface for interaction with the platform.