Understanding and Implementing Schemas in Python

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Understanding and Implementing Schemas in Python Introduction In the world of programming, particularly in the context of data management and validation, schemas play a vital role. A schema is essentially a blueprint or a predefined structure that defines the expected format, data types, and constraints for a given data entity. In this blog, we will delve into the concept of schemas in Python, exploring what they are, why they are important, and how you can implement them in your projects. What is a Schema? A schema serves as a contract between different components of a system, ensuring that data is consistent, valid, and well-structured. It defines the rules for how data should be organized, what fields it should contain, and what types of values those fields can hold. In essence, a schema acts as a set of rules that data must adhere to in order to be considered valid. Why Are Schemas Important? Data Validation: Schemas provide a way to validate incoming data. When data is received o
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How to perform case-insensitive query using Flask, SQLAlchemy and Python

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How to perform case-insensitive query using Flask, SQLAlchemy and Python

 

To perform a case-insensitive query using Flask, SQLAlchemy, and the SQLAlchemy ORM, you can use the ilike() operator provided by SQLAlchemy's filter() method. The ilike() operator is used for pattern-matching comparisons, and it performs a case-insensitive search.

Here's an example of how you can perform a case-insensitive query using Flask, SQLAlchemy, and SQLAlchemy ORM:

from flask import Flask from flask_sqlalchemy import SQLAlchemy app = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'your_database_uri' db = SQLAlchemy(app) class User(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String(50)) # Perform a case-insensitive query search_term = 'john' users = User.query.filter(User.name.ilike(f'%{search_term}%')).all() for user in users: print(user.name)

In this example, we perform a case-insensitive query on the User model using the ilike() operator. The % characters in the search term pattern allow for matching the term anywhere in the name column value. The filter() method applies the case-insensitive filter, and all() retrieves all matching records.

Note that the ilike() method is specific to SQLAlchemy and provides case-insensitive comparison. If you want to perform a case-sensitive query, you can use the like() method instead.

By using ilike() or like() methods, you can make your queries case-insensitive or case-sensitive, respectively.


Happy Learning!! Happy Coding!!

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