What is SQLAlchemy Core

What is SQLAlchemy ORM

SQLAlchemy Core is a low-level SQL toolkit provided as part of the SQLAlchemy library in Python. It provides a SQL abstraction layer, allowing you to work with SQL databases in a more Pythonic way, while still retaining full control over the SQL being executed. It is designed to be flexible, fast, and compatible with a wide range of databases, including MySQL, PostgreSQL, and SQLite.

Understanding its Features and Benefits

The Core of SQLAlchemy is a powerful and flexible low-level API that allows developers to interact directly with the database using SQL. It provides a set of classes and functions that can be used to create and execute SQL statements, giving developers fine-grained control over the database and allowing for complex queries and performance-critical applications.
One of the key features of the Core is the ability to interact directly with the database using SQL. This allows developers to have full control over the SQL statements being executed and take advantage of any database-specific features. Additionally, the Core offers flexibility in that developers can write their own SQL statements.
Another important feature of the Core is the ability to have fine-grained control over the database, including transaction management, connection management, and the ability to create and execute custom SQL statements. This is especially useful in performance-critical applications where fine-tuning database interactions can make a significant impact on performance.
Overall, the Core of SQLAlchemy is well-suited for complex queries or performance-critical applications where the ORM might not be able to handle the complexity or performance requirements. It allows for direct interaction with the database using SQL and offers fine-grained control over them, making it a valuable tool for developers.

Example

This example shows how you can use SQLAlchemy Core to create a connection to an SQLite database, execute a SELECT statement, retrieve the results, and loop through the rows. The text function is used to create a SQL expression, which is then passed to the execute method of the engine object. The fetchall method retrieves all rows from the result set as a list of dictionaries, where each dictionary represents a row and the keys are the column names.

Python3

from sqlalchemy import create_engine, text 
  
# create a connection to a SQLite database 
engine = create_engine('sqlite:///example.db') 
  
# execute a SELECT statement 
result = engine.execute(text("SELECT * FROM users")) 
  
# retrieve all rows as a list of dictionaries 
rows = result.fetchall() 
  
# loop through the rows and print the data 
for row in rows: 
    print(row) 
  
# close the connection 
result.close() 

What is the difference between SQLAlchemy Core and ORM?

SQLAlchemy Core and ORM are two different components of the SQLAlchemy library in Python. The main difference between the two is the level of abstraction they provide when working with SQL databases:

SQLAlchemy Core: It is a low-level SQL toolkit that provides a SQL abstraction layer and allows you to work directly with SQL databases using Python. It is designed to be flexible, fast, and compatible with a wide range of databases.
SQLAlchemy ORM: It is a higher-level API built on top of SQLAlchemy Core that provides an Object Relational Mapper (ORM) for working with databases. The ORM allows you to map Python classes to database tables, and to interact with the data in those tables using instances of those classes. It provides a more Pythonic and abstracted way of working with databases, making it easier for many use cases, but may not provide the same level of control and performance as SQLAlchemy Core.

In summary, SQLAlchemy Core is for those who need a low-level and flexible SQL toolkit, while SQLAlchemy ORM is for those who want a more Pythonic and abstract way of working with databases. Let’s understand it in more detail

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#Python #python