Generated Field

[Paolo Melchiorre]

Hi all,

I am at PyCon DE 2022 in Berlin with Markus and I shared with him this
idea that I have been thinking about for a few months, given his
interest I also share it with you.

I figured we could add in Django a "GeneratedField" which accepts a
"base_field" attribute in a similar way to "ArrayField" and then an
expression to generate a value for the field.

For example this model:

class Album(models.Model):
   ...
   title = models.CharField(max_length=120)
   search = GeneratedField(
     SearchVectorField(),
     F('title')
   )

would generate an SQL code like this in PostgreSQL:

CREATE TABLE album (
     ...
     title char(120),
     search tsvector GENERATED ALWAYS AS title STORED
);

I found some documentation for different database backend about
generated column (or similar names)

# SQLite
https://www.sqlite.org/gencol.html
https://www.sqlite.org/releaselog/3_31_0.html

# PostgreSQL
https://www.postgresql.org/docs/12/ddl-generated-columns.html
https://www.postgresql.org/docs/12/release-12.html

# Oracle
https://oracle-base.com/articles/11g/virtual-columns-11gr1

# MySQL
https://dev.mysql.com/doc/refman/5.7/en/mysql-nutshell.html
https://dev.mysql.com/doc/refman/5.7/en/create-table-generated-columns.html

# MariaDB
https://mariadb.com/kb/en/changes-improvements-in-mariadb-102/
https://mariadb.com/kb/en/generated-columns/

I'd love to hear your thoughts on this idea and if you think it might
be something worth continuing to investigate.

Greetings from PyCon DE 2022 in Berlin,
Paolo

--
https://www.paulox.net

-- 
You received this message because you are subscribed to the Google Groups 
"Django developers  (Contributions to Django itself)" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to django-developers+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/django-developers/CAKFO%2Bx5GHUEVdzi2awYtH5C17tTPTPh%2ByoDP%3DKC18pF8%2Bi_7PA%40mail.gmail.com.