Deletion or Insertion of Simple Large Objects

The database server cannot modify simple large objects. It can only insert or delete them. Deleting a simple large object means that the database server frees the space consumed by the deleted object for reuse.

When TEXT or BYTE data is updated, a new simple large object is created, and the data row is updated with the new blob descriptor. The old image of the row contains the descriptor that points to the obsolete value for the simple large object. The space consumed by the obsolete simple large object is freed for reuse after the update is committed. Simple large objects are automatically deleted if the rows that contain their blob descriptors are deleted. (Blobpages that stored a deleted simple large object are not available for reuse until the logical log that contains the original INSERT record for the deleted simple large object is backed up. For more information, see backing up logical-log files to free blobpages in the chapter on what is the logical log in the Informix® Administrator's Guide.)