Saving to BLOB field in dbExpress with a join
Posted on 2003-11-13
Writing to and from Interbase BLOB fields in Delphi7 like this….
...works fine until the underlying dataset is a join and the fields need to be written explicitly to the joined tables by the providers BeforeUpdateRecord event.
Building SQL statements in this event from the fields to be updated works for non-blob field but doesn’t work for BLOB fields as there is no INSERT syntax allowable for BLOB fields.
The question is therefore what should the providers BeforeUpdateRecord event look like to handle this kind of field? Is it possible to do it this way or is there another way?
A solution involving the datasets provider is preferable as this nicely encapsulates updates to all affected tables.