1. Investigation and evidence collection: The Commission for Discipline Inspection may need to investigate someone's violation of discipline and collect relevant information for investigation and evidence collection.

2. Assist in the investigation: The Commission for Discipline Inspection may need to assist other departments in the investigation and obtain relevant information to assist in the investigation.

3. Review and prosecution: The Commission for Discipline Inspection may need to review and prosecute persons suspected of violating discipline and obtain relevant information for review and prosecution.

4. Cadre management: The Commission for Discipline Inspection may need to manage cadres, and cadre management needs to collect personal data.

The specific situation needs to be judged according to the purpose, time and purpose of obtaining information. If the Commission for Discipline Inspection needs to obtain personal data, it will generally communicate with relevant personnel to inform them of their purpose and use, so as to ensure the confidentiality and security of personal data.