In scientific and design applications, updates typically require the creation of a set of database objects, which together form a complex structure exhibiting some desired property or semantics. To support this kind of data manipulation, we have extended the Daplex data manipulation language with constructs to express constraints over the creationof sets of objects. Complex update descriptions are combained with semantic and structural constraints from the database schema, and are compiled into CHIP programs which search for an update that will meet the given contraints the resulting system uses an efficient search techniques, and avoids the problems of knock-on actions found in more traditional approaches using triggers.