lisa-orm

Lisa is an ORM

Available fields now:

- CharField()
- IntegerField()
- BooleanField()
- FloatField()
- TextField()
- DateField() -> not fully ready
- DateTimeField() -> not fully ready

How to use lisa-orm:

Let's connect to database first:

# Importing models
from lisa_orm.db import models

# Path to database
db_path = 'db.sqlite3'

# Connect to database:
db = models.DB(db_path)

Ok now we are connected to database.
let's create our models:

  # Create basic system to manage classes and students 
  
  # Create classes model
  class SchoolClass(models.Model):
    table_name = 'classes'
    class_name = models.CharField(max_length=30, unique=True)
    
    def __str__(self):
        return self.name
    
  
  # Create students model
  class Student(models.Model):
    table_name = 'students'
    student_name = models.CharField(max_length=60)
    student_age = models.IntegerField()
    student_gender = models.BooleanField() # 1 for male and 0 for female
    student_class = models.ForeignKey(SchoolClass)
    
    def __str__(self):
      return self.name

Now we just defined the models.
We should apply them to database.

db.create(SchoolClass)
db.create(Student)

Congratulations. now you have two tables in database
Let's add some data to our SchoolClass model:

# create instances of SchoolClass
class_1 = SchoolClass(class_name='1-1')
class_2 = SchoolClass(class_name='1-2')
class_3 = SchoolClass(class_name='1-3')

# saving them
db.save(class_1)
db.save(class_2)
db.save(class_3)

add data to Student model:

# we can add data to foreignkey with to method:
# first: field_name__id=id. in our case will be:
# student_class__id=1
# the second is adding by reference field_name=instance
# in our case will be: student_class=class_1
# let's start:

# first we should get class that FK will reference to
class_1 = db.get(SchoolClass, id=1)

# creating instances of Student
ahmed = Student(
  student_name='ahmed mohamed',
  student_age=19,
  student_gender=1,
  student_class=class_1
)

marwan = Student(
  student_name='marwan mohamed',
  student_age=19,
  student_gender=1,
  student_class=class_1
)

asmaa = Student(
  student_name='asmaa ahmed',
  student_age=16,
  student_gender=0,
  student_class=class_1
)

# saving them
db.save(ahmed)
db.save(marwan)
db.save(asmaa)

Now we have data in our database.
let's get it:

# get one recorde
one_rec_1 = db.get(Student, id=1)
one_rec_2 = db.get(Student, student_name='marwan mohamed')
one_rec_3 = db.get(Student, id=1, student_name='ahmed mohamed')
# get return result as object of model (Student)

# filter data
filtered = db.filter(Student, student_age=19)
# filter return result as list of objects of model (Student)

We can access values by reference:

results = db .filter(Student, student_age=19)
if results: # to check if results not None
    for res in results:
        print(f'name: {res.student_name} | class: {res.student_class.class_name}')

# Output:
# name: ahmed mohamed | class: 1-1
# name: marwan mohamed | class: 1-1

We can delete models by:

db.drop(SchoolClass)
db.drop(Student)

marawan6569/lisa-orm

lisa-orm

Available fields now:

How to use lisa-orm: