>It's a little difficult to tell without comments and knowing what the properties are, but if the overlapping is happening in the child table, I check out what's happening with the line:
>

delete for empty(&llink)

this delete all recs wich gets somehow the key empty wich does not relate to parent

the overlaping are happening in parent table

ldatamaster - is alias of parent table
ldataslave - alias of child table
llink - field name common to two tables, key and foreign