Can you explain the purpose and use of the iter object in SQLAlchemy?

In SQLAlchemy, the iter object is used to iterate over query results without loading all data into memory at once. This is especially useful when working with large datasets.

For example, the Query.yield_per(n) method returns an iterator that loads data in chunks of n records, reducing memory consumption.

Example usage:

for row in session.query(User).yield_per(100):
    print(row.name)

Thus, iter allows for efficient processing of large query results, avoiding loading the entire result at once.