Checkin of a document
| Column | Type | References | Comments |
| id | Integer | Primary key | |
| vdb_id | Integer | ||
| created | Date | Date of checkin | |
| document_id | Integer | db_document.id | ID of the document for which this checkin was done |
| co_id | Integer | db_document_co.id | Corresponding checkout ID |
| release | Integer | Release number of this checkin | |
| revision | Integer | Revision number of this checkin | |
| ci_by | Integer | db_person.id | User who checked this in |
| comments | String | Comments for this checkin | |
| file_id | Integer | db_fs_file.id | File that was checked in |