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A JSON based database for python

pranavbaburaj profile image Pranav Baburaj Updated on ・2 min read

In this tutorial, we will check out a database library in python, called lol-db. Before starting this tutorial, I assume that you have a basic knowledge of python and pip. In this tutorial, we will be covering:

  • Setting up the project
  • Creating a database model
  • Other database methods

So, let's get started

Project Setup

First of all, we have to set up a python project.

  • Create a virtual environment and activate it
    Create a virtual environment
    virtualenv env
    Activate the virtual environment
    source env/bin/activate

    • Install lol-db Install lol-db using pip pip install loldb
    • Create a python file touch main.py

Introducing lol-DB

lol-DB is a python utility library that mainly contains a database and several data types. In this tutorial, we will be going through the database

To use the lol-DB module, you will have to import it into your python file

from lol.database import database, serializer
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The lol database has two main parts:

  • The database
  • The serializer

To create a new database model, you can add this code to your file

 from lol.database import database

 # Create a model
 data = database.Database("database name", ["name", "age"])
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The Database class takes two main arguments,
the name of the database(str) and an array of fields(list of str).

By default the database will create a log message every time you perform an action. To stop this, add the following lines to your code

# set track modifications
data.set_track_modification(False)

Add an item to the database

data.add(["Pranav Baburaj", 13])
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The database.add() function takes one argument
which is the list of fields

Delete an item from the database

# to get keys from the database
keys = data.ids()

# delete the last item from the database
data.delete(keys[-1])
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The delete function takes a single argument which is the id of the item. You can obtain all the keys by adding this to your code

data.ids()
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Change an item from the database

data.change(
    data.ids()[-1], # the object id
    "name", # the field name,
    "P Pranav Baburaj" # the new value
)

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Filter out elements from the database

database.filter(
    {
        "age" : 13
    }
)

# returns you the object id 
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The filter function takes a single argument, which is a dict of items to match with the database fields. The function will return a list of object ids

Get information from the database

# pass in the object id
database.get(object_id)
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Clear the database

database.clear()

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Serializers

If you are using this module along with a web framework, you may have to convert the model into either JSON format or XML. To do this you can use the database.serializer module

from lol.database import database, serialize

data = database.Database("database name", ["name", "age"])

# converting to json
print(data.jsonify())

# converting to XML
print(data.xml())
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I hope you were able to learn something new from this blog,

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Discussion (1)

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Pranav Baburaj Author

If you find any space for improving the module, please let me know