At 11:00 AM 08-02-02 +1100, Geoff wrote:

>Since you are using a blob column I suggest that there are only two
>options...
>
> 1. alter the trigger to use an appropriate UDF (there is a blob
> comparison UDF on the IBO download site)

In fact, that UDF compares two blobs, not a blob with a string. You would need to have your trigger create a "blank string blob" first before passing the two blobs to BlobCompare(). This would be relatively easy with Firebird, which can accept a string as input to a text blob, and impossible in any other version.

There are blob UDFs in FreeUDFLib, but make sure that you get the version from Claudio's site (www.cvalde.com) as the original version is buggy.

> 2. alter the triggers so that it does not check for blank strings

Unless you have some forced reason to store a blank string in a blob, i.e. a NOT NULL constraint on a blob column and your app pushing through a blank blob as a default, then your trigger can simply ignore null blobs. Even so, under some conditions, I suppose, you would still need to check for a blank blob if your application code doesn't prevent the user from storing them.


regards,
Helen Borrie (TeamIBO Support)

** Please don't email your support questions privately **
Ask on the list and everyone benefits
Don't forget the IB Objects online FAQ - link from any page at www.ibobjects.com