Databases management

In this section, you will learn how to use the databases that come along with the microfading package and inside which you have the possibility to store information. The main purpose of the databases is to connect the metadata with the analytical data. Additionally, the databases will allow you to conveniently reuse information and will also enable you to perform queries based on the information stored in the databases. For example, one could retrieve all the data obtained on paintings created by a given artist.

This section implies that you have created the database files. If that is not the case, look at the section on how to create empty databases. If you want to know whether databases were already created, use the following function:

import microfading as mf

# Check whether databases were created.
mf.is_DB()

True
All the databases were created and can be found in the following directory: /home/john/Documents/MFT/databases

Description¶

The databases simply consists of csv and txt files (Table 1) inside which you will accumulate information. The management of the databases lies around two main actions:

You want to learn how to add / remove info.
You want to learn how to retrieve info.

The first things to do is to import the microfading package as showed in the code box above. You will access the databases functions as followed: mf.<function name>

# for example, this will retrieve all the microfading devices that you registered. 
mf.get_devices()

Every function name start with a verb followed by an underscore and a noun or an adjective providing more information about the action that will be performed. There are only 4 verbs:

Get: retrieve information contains in the databases
Add: add a new item in the databases (in future versions, I will implement remove functions)
Update: modify the recorded parameters of the databases
Set: set default values for some key parameters

Table 1. Description of the database files.

Filename	Description
DB_objects.csv	Contain information related to each microfaded object
DB_projects.csv	Contain information related to each project
institutions.txt	Contain information about the owners (institutions) of the objects
MFT_devices.txt	Contain information about the microfading devices
objects_creators.txt	A list of persons (surname and name) that created the objects
objects_supports.txt	A list of a materials used to create the objects
objects_techniques.txt	A list of techniques used to create the objects
objects_types.txt	A list of global categories to define the objects
persons.txt	A list of persons (name, surname, and initials) performing the analyses
white_standards.txt	Contain information related to white reference standards

Get functions¶

Table 2. Description of the get functions.

Function name	Description
`get_path_DB()`	returns the absolute path where the databases are stored on your local computer
`get_DB()`	eturns the databases as pandas dataframes
`get_colorimetric_info()`	returns the observer and illuminant default values
`get creators()`	returns a list of names and surnames corresponding to the persons that created the microfaded objects
`get_datasets()`	returns a list of microfading example data filenames that can be used to try the package
`get_institutions()`	returns a list of institutions that own the microfaded objects
`get_lighting_conditions()`	returns the default light exposure conditions default values
`get_objects()`	returns a list of the microfaded objects
`get_persons()`	returns a list of persons that performed the microfading analyses
`get_devices()`	returns a list of the registered microfading devices
`get_white_standards()`	returns a list of the registered white standard references

Add functions¶

Table 3. Description of the add functions.

Function name	Description
`add_new_creator()`	record information about a new object creator (artist, institution, etc.)
`add_new_institution()`	record information about a new institution
`add_new_object()`	record information about a new object
`add_new_person()`	record information about a new person performing microfading measurements.
`add_new_project()`	record information about a new project
`add_devices()`	add a new microfading device
`add_reference()`	add a new white standard reference

Set functions¶

+Table 4. Description of the set functions.

Function name	Description
`set_colorimetric_info()`	set the observer and illuminant default values
`set_DB()`	set the use of databases (True or False)
`set_dose_unit()`	set the unit of the light dose (MJ/m2, Mlxh, or sec)
`set_folder_DB()`	set the path of the databases files should be stored
`set_lighting_conditions()`	set the light exposure conditions default values

The values defined in the set functions are stored inside the db_config.json file which you can find on your local computer inside the site-packages folder of Anaconda. The folder site-packages is where the python libraries are installed on your computer (see below).

import microfading as mf

# This command will indicate you where is the microfading package installed on your computer
mf

 < module 'microfading' from '/home/john/anaconda3/lib/python3.11/site-packages/microfading/__init__.py'>

Whenever a function will need a parameter stored inside the db_config.json, it will retrieve it and use it (See code below for an example).

Update functions¶

Table 5. Description of the update functions.

Function name	Description
`update_DB_objects()`	add new categories to the objects database
`update_DB_projects()`	add new categories to the projects database