Django db_index=true

When we should use db_index=True in Django?

This is not really django specific; more to do with databases. You add indexes on columns when you want to speed up searches on that column.

Typically, only the primary key is indexed by the database. This means look ups using the primary key are optimized.

If you do a lot of lookups on a secondary column, consider adding an index to that column to speed things up
I would say you should use db_index=True when you have a field that is unique for more useful lookups.

For example if you a table customers with records of many users they'll each have their own unique user_id. 
Each user_id would be unique and having to index this field to find that unique user is more often desirable than say their first_name or last_name.
Actually this is also ok but since they're not unique you will get probably recieve multiple results from your queries and this might not be as useful as using an referencing their id.

Similar codes

1 vote234 views1 answer
Animations text terminal python
Python
24 votes230 views6 answers
Create a timestamp python
Python
1 vote234 views1 answer
Discord.py check if message has certain reaction
Python
0 vote239 views1 answer
Import "sendgrid" could not be resolved django
Python
-1 vote228 views1 answer
How to transcode a video in python using ffmpeg
Python
3 votes235 views2 answers
Python append row to 2d array
Python
1 vote213 views1 answer
How to convert character to factor in python
Python
1 vote247 views2 answers
Python write json to file utf8
Python
1 vote233 views1 answer
Matplotlib change bar color under threshold
Python
0 vote239 views1 answer
Numpy get length of list
Python