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<p>
If you modify the object to which an iterator refers by
(*iterator).member_function_call() or (*iterator).data_member = new_value,
you should call iterator->_DB_STL_StoreElement() to store the change,
otherwise the change would be lost after the iterator moves on to
other elements.
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<p>
If you are storing a sequence, and you modified some part of it, you
should also call this function before the iterator moves.
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<p>
And in both cases, if you
specified <span class="bold"><strong>directdb_get</strong></span> as true (this
is the default value), you should call _DB_STL_StoreElement() after
the change and before the next iterator movement OR the next
dereferencing of the iterator by the star or arrow operators, i.e.
iterator::operator* or iterator::operator->,
otherwise the change is also lost.
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<p>
If you update the element by assigning to a dereferenced iterator like
this: <span class="bold"><strong>*iterator = new_element;</strong></span> then you never
have to call _DB_STL_StoreElement(), the change is stored to the
database automatically.
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