id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
36889	cursor_iter() docstring could use more detail about parameters and behavior	Muhammed irshad ismail		"While reading through {{{django/db/models/sql/compiler.py}}}, I came across the
{{{cursor_iter()}}} helper. The implementation itself is quite small, but some
important details aren’t obvious from the current docstring.

Here is the current implementation:

{{{
def cursor_iter(cursor, sentinel, col_count, itersize):
""""""
Yield blocks of rows from a cursor and ensure the cursor is closed when
done.
""""""
try:
for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
yield rows if col_count is None else [r[:col_count] for r in rows]
finally:
cursor.close()
}}}

While reading this, a few things were not immediately clear without stepping
through the code:

what the {{{sentinel}}} value represents and how it is used to stop iteration

* why {{{col_count}}} is needed and when rows are sliced

* what the function actually yields (an iterator yielding batches of rows)

* that the cursor is always closed via {{{finally}}}, even if iteration stops
   early or an error occurs

Expanding the docstring to briefly explain:

* each parameter

* the return value

* and the cursor-closing guarantee

would make this helper easier to understand for contributors working on the SQL
compiler internals, without changing any behavior.

This would be a documentation-only improvement."	Cleanup/optimization	new	Documentation	6.0	Normal				Unreviewed	0	0	0	0	0	0