How to bulk add information to the profiles of users? I have hundreds user profiles where I want to add a one or two fields like the adress of the company they work for. For some group of users this adress will be the same and for others it will be different. How do I mass bulk add these kind of informations? Through the database? (I'm on phpmyadmin)
Step 1

Use the Rules module to create a Rules Component, which includes whatever Rules Conditions you might need (if any), and with a Rules Action to Set a data value, for each of those fields you want to be updated.

Step 2

Create a view of the group of users for which those fields should be added. Then transform that view into a view that uses Views Bulk Operations, and use the technique documented in "How to use Rules to create a custom bulk operation for a VBO view?". In doing so, you'll then be able to use the Rules Component from Step 1.

Tutorial

To get the idea, have a look at the video about Using Rules components with VBO" which uses a Rules Component with (only) 1 parameter. If you want even more, then also watch the subsequent "Using Rules components with more than one parameter" video.

Attention: to process like 100.000 entities at once is quite a challenge (memory requirements, etc). Therefor you might want to also watch the video about "More details about VBO settings" ... Before you are tempted to use VBO for processing them all at once ...

PS: this answer is for D7 ...