How Can We Bypass Workflow Rules When Using The Salesforce Data Loader?

Hi Manpreet

Deactivating triggers and validation rules may be a solution if you don’t have to do that every day.
A best alternative is to include that in your business logic having an hidden checkbox you set to TRUE when you want to bypass the triggers, validation rules and workflow.
Then, you have to ckeck the value of this field for every component you want to allow the bypass.y

you can refer to this link

https://developer.salesforce.com/forums/ForumsMain?id=906F00000009FRoIAM

hope it may help you