Optimize Cursor.fetchall

[rostan-t]

The method Cursor.fetchall has the following docstring :

Fetch all (remaining) rows of a query result, returning them as a sequence of sequences (e.g. a list of tuples). Note that the cursor's arraysize attribute can affect the performance of this operation. However, the method's implementation is simply :

return list(self)

which creates a list by calling self.fetchone, i.e. self._results.pop(0), once for each element of the list self._results.

This is a performance issue and can be done more straightforwardly.

[navina]

@RostanTabet : Iiuc, you are proposing to return a copy of the internal list object (_results) instead of letting the python's in-built list to construct a list instance by iterating through the objects. Is that right?

I am not that familiar with python internals. Does results = self._results create a copy of the list and assign to the lhs results variable ? Or is it just returning a reference to the list _results ?

[xiangfu0]

Can you please rebase and we can merge this.