static VALUE cDB_vsiz(VALUE vself, VALUE vkey){
TCRDB *db;
Data_Get_Struct(rb_iv_get(vself, RDBVNDATA), TCRDB, db);
vkey = StringValueEx(vkey);
return INT2NUM(tcrdbvsiz2(db, RSTRING_PTR(vkey)));
}
bool key_exists(const char *key) {
if (use_cabinet_lib) return tchdbvsiz2(hdb, key) > 0;
else return tcrdbvsiz2(tdb, key) > 0;
}
