Hello,

I am very surprised when I introduce a variable as key/data length
because the function get() alter the key/data length value. Due to this
problem I have to do reset the value of key/data length.

Could some one tell me in which case get() alter the key/data length
value. My database have fix length key/data that does not cause buffer
too small error.
The fact to reset each time the key/data length value cause loss of
performance.

This is a sample of my code:

int key_data_length= sizeof(int); // I think this line is sufficient.
while ( get(&key, key_data_length, DB_NEXT_NODUP) )
{
while ( get(&key, key_data_length, DB_NEXT_DUP) );
key_data_length = sizeof(int);
// Why this last line ??? This decrease performance.
// Why the get() change the key_data_length. Note that all
// data/key in my data base are fixed length to int.
//
}

Thank you.

Hi,

If this "get" is a function you have implemented that calls DB, there
is no way that it could be modifying key_data_length, since you are
passing by value.

If this is shorthand for a call to this cursor method:

dbc->c_get(dbc, &key, key_data_length, DB_NEXT_NODUP)

then I'm surprised that it compiles. Aren't there warnings?

The third parameter in this call (where you are passing key_data_lenth)
should be a pointer to a DBT that will hold the data value part of the
key/data pair.

If I've misunderstood, can you please post the code that actually makes
the call to Berkeley DB?

Regards,
Michael.