polars.DataFrame.lazy¶
- DataFrame.lazy() polars.internals.lazy_frame.LazyFrame[polars.internals.frame.DF] ¶
Start a lazy query from this point. This returns a LazyFrame object.
Operations on a LazyFrame are not executed until this is requested by either calling:
.fetch() (run on a small number of rows)
.collect() (run on all data)
.describe_plan() (print unoptimized query plan)
.describe_optimized_plan() (print optimized query plan)
.show_graph() (show (un)optimized query plan) as graphiz graph)
Lazy operations are advised because they allow for query optimization and more parallelization.