sqlitemodel is a wrapper for the sqlite3 database that enables you to create models you can easily save, query and retrieve from the database.
This is build with three classes who abstract the database communication and the object management.
Install through pip.
$ pip install sqlitemodel
or get from source
$ git clone https://github.com/gravmatt/sqlitemodel.git
$ cd sqlitemodel
$ python setup.py install
Class to abstract the model communication with the database.
Import
from sqlitemodel import Model, Database
# IMPORTANT
Database.DB_FILE = 'path/to/database.db'
Set the path to the database when your application starts or before you try to accessing the database.
Building a user class that inherits the Model class to show how it works.
class User(Model):
def __init__(self, id=None):
Model.__init__(self, id, dbfile=None, foreign_keys=False, parse_decltypes=False)
self.firstname = ''
self.lastname = ''
self.age = ''
# Tries to fetch the object by its rowid from the database
self.getModel()
# Tells the database class the name of the database table
def tablename(self):
return 'users'
# Tells the database class more about the table columns in the database
def columns(self):
return [
{
'name': 'firstname',
'type': 'TEXT'
},
{
'name': 'lastname',
'type': 'TEXT'
},
{
'name': 'age',
'type': 'INTEGER'
}
]
The two methods tablename() and columns() are required, to map the table columns with the Model objects.
id argument and the getModel() method in the constructor are optional.
It also possible to use the selectCopy() method to query for any data in the database table and fill the model object with the result.
selectCopy(SQL() | raw_sql_query_string)
Ex:
class User(Model):
def __init__(self, id=None, email=None):
Model.__init__(self, id)
if(email):
self.selectCopy(SQL().WHERE('email', '=', email))
The Model class constructor has an optional dbfile argument. If it is set, the static variable Database.DB_FILE is ignored.
Creating a new User
# create a new user
user = User()
# creating the table inside the database
user.createTable()
# add infos about the user
user.firstname = 'Rene'
user.lastname = 'Tanczos'
user.age = 25
# save the user into the database
user.save()
Retriving the User from the database
# get it by id
user = User(1)
# get the user by his firstname and lastname
# User().selectOne(SQL())
user = User().selectOne(SQL().WHERE('firstname', '=', 'Rene').AND().WHERE( 'lastname', '=', 'Tanczos'))
# Or get more the one user
# this method will return an array of matching users
users = User().select(SQL().WHERE('age', '=', 25))
Class to build SQL query to reduce misspelling and to abstract this problem a bit.
Import
from sqlitemodel import SQL
INSERT
sql = SQL().INSERT('users').VALUES(firstname='Rene', lastname='tanczos')
print sql.toStr()
# INSERT INTO users (firstname,lastname) VALUES (?,?);
print sql.getValues()
# ('Rene', 'tanczos')
UPDATE
sql = SQL().UPDATE('users').SET('firstname', 'Rene').SET('lastname', 'Tanczos').WHERE('firstname', '=', 'Rene').AND().WHERE('lastname', '=', 'Tanczos')
print sql.toStr()
# UPDATE users SET firstname=?, lastname=? WHERE firstname=? AND lastname=?;
print sql.getValues()
# ('Rene', 'Tanczos', 'Rene', 'Tanczos')
SELECT
sql = SQL().SELECT('name', 'age', 'size').FROM('users').WHERE('age', '=', 27).AND().WHERE('size', '<', 190).ORDER_BY('age', 'ASC').LIMIT(0, 10)
print sql.toStr()
# SELECT name, age, size FROM users WHERE age=? AND size<? ORDER BY age ASC LIMIT 0,10;
print sql.getValues()
# (27, 190)
WHERE
The WHERE method has a optional isRaw parameter.
If set to True, the SQL class paste the value directly into the sql query and does not use the ? symbol.
WHERE('size', '<', 190, isRaw=True)
DELETE
sql = SQL().DELETE('users').WHERE('id', '=', 4)
print sql.toStr()
# DELETE FROM users WHERE id=?;
print sql.values
# (4,)
Represents the database.
First you should set the database file path to your sqlite3 database.
Don't worry if it doesn't exist yet. Sqlite3 automatically creates a database file on the selected path if it doesn't exists.
from sqlitemodel import Database
It is recommended to set the path to the database after starting the application by the static variable inside the Database class.
Database.DB_FILE = 'path/to/database.db'
db = Database()
But the path can be also set inside the Database constructor while the object initializes.
db = Database('path/to/database.db')
The Database class supports the with statement whitch is recommended to use.
with Database() as db:
users = db.select(SQL().SELECT().FROM('users'))
The database connection get automatically closed after the with block is processed.
All of this method using a Model object as first argument, so that the Database object knows how to use it.
close()
# close connection
createTable(model)
# create the database table if not exists by the the model object
save(model)
# create or update a model object and return it id
delete(model)
# delete a model object and return True/False
select(model, SQL() | sql query , values=())
# return a array of the given model
selectOne(model, SQL() | sql query, values=())
# return the first matching entry of the given model
selectById(model, id)
# return the a model object by his id
If there is some data without a Model, it can be retrieved as raw data of a list or list of Dict objects.
getRaw(SQL() | sql query, values=(), max=-1)
# return an array of results.
# index 0 is the header of the table
getDict(SQL() | sql query, values=(), max=-1)
# return a list array with a Dict object.
# the key of the Dict object is the column name
To count the results of a query, the method zeroZero() can be used.
zeroZero(SQL() | sql query)
# It return the the first column of the first line ( result[0][0] )
# That why the method is called zeroZero()
To check if a table or column exists, the functions table_exists() and column_exists() can be used. Both will return a boolean value if the table/column was found or not.
table_exists('tablename')
# True or False
column_exists('tablename', 'column_name')
# True or False
The MIT License (MIT)
Copyright (c) 2016-2017 René Tanczos
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.