in Salesforce, users might setup validation rules to help enter good data(complete data) in the system.A record can be inserted in system via the UI and also programatically.
A trigger can also be used to create a record, in such scenarios - there may be a need to bypass an existing validation rule which might not be a required on when creating this record thru code.
In such situations, you can bypass validation rules using methods discussed in the following links:http://bobbuzzard.blogspot.sg/2011/11/bypass-validation-rules-from-apex.html http://salesforce.stackexchange.com/questions/44290/how-to-bypass-validation-rule-for-trigger-in-salesforce
A trigger can also be used to create a record, in such scenarios - there may be a need to bypass an existing validation rule which might not be a required on when creating this record thru code.
In such situations, you can bypass validation rules using methods discussed in the following links:http://bobbuzzard.blogspot.sg/2011/11/bypass-validation-rules-from-apex.html
http://salesforce.stackexchange.com/questions/44290/how-to-bypass-validation-rule-for-trigger-in-salesforce