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Insure that memo fields that store text only are identified as field a type of ftMemo (the default for 'M' field types), and that memo fields that are to contain BLOB data only are identified as a type of ftBlob (not ftGraphic or otherwise). These settings can be specified by double-clicking on the TApolloTable object at design-time to bring up the fields editor. Add the fields to the field list (i.e. right-click, add fields). Then select each memo field and specify the BlobType property value in the Object Inspector.

 

You can also define the BlobType of a memo field at run-time like this:

 

(ApTbl.FieldByName('MYBLOB') as TBlobField).BlobType := ftBlob; 

Deleting a Reference to BLOB Data

To delete the actual reference to a BLOB field, call the API function sx_PutBLOB() as follows:

 

var

wa : integer; 

begin

 // use the table's handle property to prepare the API

 sx_Select( apTable1.Handle );

 sx_PutBlob( 'BLOBFLD', Pointer(0), 0);

end;

The BLOB data itself is not deleted until the table is packed.