BDE-enabled datasets all have a CacheBlobs property that controls whether BLOB fields are cached locally by the BDE when an application reads BLOB records. By default, CacheBlobs is True, meaning that the BDE caches a local copy of BLOB fields. Caching BLOBs improves application performance by enabling the BDE to store local copies of BLOBs instead of fetching them repeatedly from the database server as a user scrolls through records. 

In applications and environments where BLOBs are frequently updated or replaced, and a fresh view of BLOB data is more important than application performance, you can set CacheBlobs to False to ensure that your application always sees the latest version of a BLOB field.