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  * __
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  * polars.LazyF... 

#  polars.LazyFrame.merge_sorted  #

LazyFrame.  merge_sorted  (  _ other  :  LazyFrame  _ , _ key  :  [ str
](https://docs.python.org/3/library/stdtypes.html#str "\(in Python v3.12\)") _
)  →  Self  [ [source]  ](https://github.com/pola-rs/polars/blob/main/py-
polars/polars/lazyframe/frame.py#L5802-L5866) #

    

Take two sorted DataFrames and merge them by the sorted key.

The output of this operation will also be sorted. It is the callers
responsibility that the frames are sorted by that key otherwise the output
will not make sense.

The schemas of both LazyFrames must be equal.

Parameters  :

    

**other**

    

Other DataFrame that must be merged

**key**

    

Key that is sorted.

Examples

    
    
    >>> df0 = pl.LazyFrame(
    ...     {"name": ["steve", "elise", "bob"], "age": [42, 44, 18]}
    ... ).sort("age")
    >>> df0.collect()
    shape: (3, 2)
    ┌───────┬─────┐
    │ name  ┆ age │
    │ ---   ┆ --- │
    │ str   ┆ i64 │
    ╞═══════╪═════╡
    │ bob   ┆ 18  │
    │ steve ┆ 42  │
    │ elise ┆ 44  │
    └───────┴─────┘
    >>> df1 = pl.LazyFrame(
    ...     {"name": ["anna", "megan", "steve", "thomas"], "age": [21, 33, 42, 20]}
    ... ).sort("age")
    >>> df1.co