Contenu du cours

Django ORM Ninja: Advanced Techniques for Developers

1. Introduction to Django ORM

Introduction to the Course Introduction to the ORM Start a New Project Initialize a New Project

2. Models, datatypes, and fields

Defining The First Model Field Data Types Define Other Models Migrations Admin Interface

3. Queries

Create Query Retrieve Query Lazy Queries Ordering and Slicing Updating Deleting

4. Relations

Many-to-One ForeignKey Arguments One-to-One Many-to-Many

5. Complex Queries

Field Lookups Q and F Objects Aggregations Annotations Minimazing Database Hints

6. Advanced

Class Meta Constrains Transactions Basics User Model

Field Lookups

A field lookup is essentially a way to specify how Django should filter query results based on a model field's value.

Basic Structure

A field lookup takes the form field__lookuptype=value. Here, field is the name of the model field, lookuptype is the type of comparison, and value is the value to compare against.

Common Field Lookups

exact - the default lookup type; it performs case-sensitive comparisons.
( SELECT * FROM Book WHERE genre = 'philosophy'; )

python

iexact - case-insensitive match.
( SELECT * FROM Author WHERE LOWER(pen_name) = LOWER('george orwell'); )

python

contains - case-sensitive containment test.
( SELECT * FROM Book WHERE title LIKE '%House%'; )

python

icontains - case-insensitive containment test.
( SELECT * FROM Book WHERE LOWER(title) LIKE LOWER('%house%'); )

python

in - in a given iterable; often used for filtering by a list of values.
( SELECT * FROM Author WHERE id IN (1, 4, 7); )

python

gt , gte , lt , lte - greater than, greater than or equal to, less than, and less than or equal to.
( SELECT * FROM Author WHERE id < 10; )

python

startswith , istartswith - string starts with a value (case-sensitive and insensitive versions).
( SELECT * FROM Author WHERE first_name LIKE 'J%'; )

python

endswith , iendswith - string ends with a value (case-sensitive and insensitive versions).
( SELECT * FROM Author WHERE last_name LIKE '%e'; )

python

range - within a certain range (inclusive).
( SELECT * FROM Book WHERE id BETWEEN 1 AND 5; )

python

date , year , month , day - specific date components.
( SELECT * FROM Book WHERE EXTRACT(YEAR FROM pub_date) = 2023; )

python

1. What is the default field lookup type in Django?

2. How do you filter a queryset to include records where the field value starts with a certain string, case-sensitively?

3. What does the lookup 'pk__lt=10' signify?

What is the default field lookup type in Django?

Select the correct answer

contains

iexact

exact

How do you filter a queryset to include records where the field value starts with a certain string, case-sensitively?

Select the correct answer

Model.objects.filter(field__endswith='value')

Model.objects.filter(field__startswith='value')

Model.objects.filter(field__istartswith='value')

Model.objects.filter(field__contains='value')

What does the lookup 'pk__lt=10' signify?

Select the correct answer

Select records with a primary key less than or equal to 10.

Select records with a primary key greater than 10.

Select records with a primary key equal to 10.

Select records with a primary key less than 10.

Tout était clair ?

Comment pouvons-nous l'améliorer ?

Merci pour vos commentaires !

Section 5. Chapitre 1

Demandez à l'IA

Posez n'importe quelle question ou essayez l'une des questions suggérées pour commencer notre discussion

Contenu du cours

Django ORM Ninja: Advanced Techniques for Developers

1. Introduction to Django ORM

Introduction to the Course Introduction to the ORM Start a New Project Initialize a New Project

2. Models, datatypes, and fields

Defining The First Model Field Data Types Define Other Models Migrations Admin Interface

3. Queries

Create Query Retrieve Query Lazy Queries Ordering and Slicing Updating Deleting

4. Relations

Many-to-One ForeignKey Arguments One-to-One Many-to-Many

5. Complex Queries

Field Lookups Q and F Objects Aggregations Annotations Minimazing Database Hints

6. Advanced

Class Meta Constrains Transactions Basics User Model

Field Lookups

A field lookup is essentially a way to specify how Django should filter query results based on a model field's value.

Basic Structure

A field lookup takes the form field__lookuptype=value. Here, field is the name of the model field, lookuptype is the type of comparison, and value is the value to compare against.

Common Field Lookups

exact - the default lookup type; it performs case-sensitive comparisons.
( SELECT * FROM Book WHERE genre = 'philosophy'; )

python

iexact - case-insensitive match.
( SELECT * FROM Author WHERE LOWER(pen_name) = LOWER('george orwell'); )

python

contains - case-sensitive containment test.
( SELECT * FROM Book WHERE title LIKE '%House%'; )

python

icontains - case-insensitive containment test.
( SELECT * FROM Book WHERE LOWER(title) LIKE LOWER('%house%'); )

python

in - in a given iterable; often used for filtering by a list of values.
( SELECT * FROM Author WHERE id IN (1, 4, 7); )

python

gt , gte , lt , lte - greater than, greater than or equal to, less than, and less than or equal to.
( SELECT * FROM Author WHERE id < 10; )

python

startswith , istartswith - string starts with a value (case-sensitive and insensitive versions).
( SELECT * FROM Author WHERE first_name LIKE 'J%'; )

python

endswith , iendswith - string ends with a value (case-sensitive and insensitive versions).
( SELECT * FROM Author WHERE last_name LIKE '%e'; )

python

range - within a certain range (inclusive).
( SELECT * FROM Book WHERE id BETWEEN 1 AND 5; )

python

date , year , month , day - specific date components.
( SELECT * FROM Book WHERE EXTRACT(YEAR FROM pub_date) = 2023; )

python

1. What is the default field lookup type in Django?

2. How do you filter a queryset to include records where the field value starts with a certain string, case-sensitively?

3. What does the lookup 'pk__lt=10' signify?

What is the default field lookup type in Django?

Select the correct answer

contains

iexact

exact

How do you filter a queryset to include records where the field value starts with a certain string, case-sensitively?

Select the correct answer

Model.objects.filter(field__endswith='value')

Model.objects.filter(field__startswith='value')

Model.objects.filter(field__istartswith='value')

Model.objects.filter(field__contains='value')

What does the lookup 'pk__lt=10' signify?

Select the correct answer

Select records with a primary key less than or equal to 10.

Select records with a primary key greater than 10.

Select records with a primary key equal to 10.

Select records with a primary key less than 10.

Tout était clair ?

Comment pouvons-nous l'améliorer ?

Merci pour vos commentaires !

Section 5. Chapitre 1