Casting to Smart Large Objects

The database server provides casts to allow the conversion of TEXT and BYTE objects to BLOB and CLOB data types. This feature allows users to migrate BYTE and TEXT data from legacy databases into BLOB and CLOB columns.

The following example shows how to use an explicit cast to convert a BYTE column value from the catalog table in the stores_demo database to a BLOB column value and update the catalog table in the superstores_demo database:

UPDATE catalog SET advert = ROW (
(SELECT cat_photo::BLOB FROM stores_demo:catalog 
   WHERE catalog_num = 10027), 
   advert.caption)
      WHERE catalog_num = 10027

The database server does not provide casts to convert BLOB to BYTE values or CLOB to TEXT values.