Ned Ludd nedludd0
nedludd0
/ gist:a9f3fe9cf138c423befa50ba89d40c55
Last active
February 5, 2021 11:29
— forked from hest/gist:8798884
Fast SQLAlchemy counting (avoid query.count() subquery)
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| # https://gist.github.com/hest/8798884 | |
| def get_count(q): | |
| count_q = q.statement.with_only_columns([func.count()]).order_by(None) | |
| count = q.session.execute(count_q).scalar() | |
| return count | |
| q = session.query(TestModel).filter(...).order_by(...) | |
| # Slow: SELECT COUNT(*) FROM (SELECT ... FROM TestModel WHERE ...) ... |