iterselects break if not immediately used

[emman27]

Minimal example:

collection1 = db(db.table1.id > 0).iterselect(...)
collection2 = db(db.table2.id > 0).iterselect(...)
for row in collection1:
    do_something()
for row in collection2:
    do_something() # breaks

Root cause:
When the iterselect (IterRows) object is initialized, it is given a gluon.contrib.pg8000.core.Cursor attribute on iter_rows._c. At the same time, the attribute iter_rows.db._adapter is given the same Cursor.
However, since db._adapter only keeps track of the latest Cursor, after the iteration of collection1, the Cursor of db._adapter is closed - then collection2 has no cursor anymore, and cannot execute the query.

[BuhtigithuB]

Is this related to pg8000 only or it is present in psycopg2 too??

If it limited to pg8000, consider closing this issue as pg8000 support have been droped :

d4d7e48

https://github.com/web2py/web2py/pull/1871/files#diff-0

Thanks

[niphlod]

I don't know if it's possible at all to keep two iterating cursors on the same adapter