Object Relational Mapping (ORM) is a technology that allows programming in Object-oriented programming languages (such as python) and relational database for seamless interaction. One of the most popular ORM libraries in the Python language is sqlAlchemy, which is constantly updated and enhanced to provide new features and improved performance.
the latest update
SQLAlchemy 2.0
- Improving performance: Significantly improves query speed by using technologies such as asynchronous io and parallel execution.
- New query API: Introduces new query api, providing a more concise and intuitive way to build complex queries.
- Enhanced transaction management: Improved support for transactions , including distributed transactions and nested transactions.
- ORM extension pluggability: Provides a highly pluggable ORM extension system, allowing easy integration of third-party libraries.
SQLAlchemy 1.4
- JSON Extension: Added native support for the JSON data type, allowing seamless processing of jsON data.
- Asynchronous support: Provides comprehensive support for asynchronous programming , including asynchronous database connection pooling and asynchronous query execution.
-
ORM mapping improvements: Introduced new mapping options such as
@validates()
for performing custom validations during the object lifecycle.
characteristic
Dynamic query construction
SQLAlchemy allows building queries in a dynamic and type safe way. Queries can be constructed using Python code and then modified or customized as needed.
Relationship Modeling
SQLAlchemy provides rich relationship modeling capabilities, allowing the definition of complex data models, including one-to-one, one-to-many, and many-to-many relationships.
Data loading strategy
SQLAlchemy provides flexible data loading strategies that allow lazy or eager loading of related objects. This improves performance while allowing data loading behavior to be customized as needed.
Query optimization
SQLAlchemy uses automatic query optimization techniques such as delayed execution and batching to improve query performance. Additionally, it provides options such as with_polymorphism()
and slice()
for further optimization of queries.
Transaction Management
SQLAlchemy provides robust transaction management capabilities, including support for nested transactions and distributed transactions. It also provides session and connection management tools to simplify database interaction.
ORM extensionSQLAlchemy provides an extensible ORM system that allows easy integration of third-party libraries and extensions. This increases flexibility, allowing the addition of custom features such as version control, full-text search or
caching.
Future OutlookSQLAlchemy's
developmentteam is committed to providing continuous updates and improvements. Future releases are expected to focus on further improving performance, enhancing the query API, and providing additional ORM extensions.
in conclusionSQLAlchemy ORM is a powerful tool for Python developers working with relational databases. With constant updates and the introduction of new features, it maintains its leadership in the ORM space, providing developers with seamless data interaction, improved performance, and flexible scalability to meet complex application requirements.
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